JP4062832B2 - Data recording / reproducing apparatus and data recording / reproducing method - Google Patents

Description

【０１０１】
Audio_Validity_Flagは、オーディオデータが有効のとき“0”を示し、無効のときの“1”を示す１ビットの情報である。
Audio_Source_Analog_Flagは、オーディオデータのソースがアナログ信号であるかどうかを示す１ビットの情報である。ソースがアナログ信号の場合は“1”とし、デジタル信号の場合は、“0”とする。
Duplicate_Flagは、このレコーディングユニットの始めの部分又は終わりの部分に、他のレコーディングユニットと重複するデータ（のりしろデータ）が含まれているかどうかを示す２ビットの情報である。のりしろデータが無い場合には“00”とし、始めの部分にのりしろデータが含まれている場合には“01”とし、終わりの部分にのりしろデータが含まれている場合には“10”とし、始め及び終わりの部分にのりしろデータが含まれている場合には“11”とする。
Number_of_GOPは、このレコーディングユニットに含まれているＧＯＰの数を示す４ビットの情報である。
Number_of_Audio_Quantization_Bitは、オーディオデータの量子化ビットを示す４ビットの情報である。Number_of_Audio_Quantization_Bitでは、具体的には以下のような情報を示す。
“0000”は量子化ビットが１６ビットであるを示し、“0001”は１７ビット、“0010”は１８ビット、“0011”は１９ビット、“0100”は２０ビット、“0101”は２１ビット、“0110”は２２ビット、“0111”は２３ビット、“1000”は２４ビット、その他はリザーブを示す。
Audio_Coding_Flagは、オーディオデータの符号化情報を示す２ビットの情報である。MPEG Audio Layer IIの場合は“00”とし、Linear PCMの場合は“01”とする。
mark_bitは、予備のビットである。
【０１０２】
Number_of_Audio_Frameは、ＧＯＰに含まれるオーディオフレームの数を示す５ビットの情報である。のりしろデータが含まれたオーディオフレーム分も含む。
PTS_FSは、オーディオフレームの出力タイミングを、ビデオリファレンスフレームとの相対位相で表す１１ビットの情報である。PTS_FSは、このＭＰＥＧ−２データストリームとは別のストリームとして記録されるヘッダデータにのみ記録される。
Audio_PTSは、各オーディオフレームのＰＴＳ（Presentation Time Stamp）を示す３３ビットの情報である。ＰＴＳは、９０ｋＨｚ精度でオーディオフレームの出力時間を表すものである。
なお、以上のNumber_of_Audio_FrameとPTS_FSとAudio_PTSとは、ＧＯＰ単位で付加される情報である。
【０１０３】
Audio_Frame_Stream_byte_Lengthは、オーディオデータのバイト数を示す１６ビットの情報である。
【０１０４】
Audio_Frame_Crcc_Flagは、オーディオフレーム単位でCrccコードが有効であるかを示す１ビットの情報である。
【０１０５】
Audio_32bitAlign_byte_Lengthは、オーディオデータのバイト数を４の倍数にするために付加する２ビットの追加バイトである。
Edit_Flagは、このオーディオフレームでエディットされたことを示す情報である。“00”はエディットされていなことを示し、“01”はｉｎ点であることを示し、“10”はアウト点であることを示し、“11”はリザーブである。
【０１０６】
以上のAudio_Frame_Stream_byte_LengthからEdit_Flagまでの情報は、オーディオフレーム毎に付加される情報である。
【０１０７】
Audio_Layer_Header_Crccは、８ビットのAudio_Layer_Header_のCrccコードである。Crccは、Audio_Layer_Headerの先頭から１byte毎にAudio_Layer_header_byte_Length-1までを計算し、最後に１バイトのCrccコードを付加する。Crccが無効の場合は、“00h”とする。
【０１０８】
つぎに、AUX_Layer_Headerの内容について説明する。図８にAudio_Layer_Headerのデータ構造を示す。
【０１０９】
AUX_Layer_Header_byte_Lengthは、AUX_Layer_Headerのバイト数を示す１６ビットの情報である。
AUX_Layer_Header_Crcc_Flagは、AUX_Layer_HeaderのCrccコードが有効であるかを示す１ビットの情報である。
Number_of_GOPは、このレコーディングユニットに含まれるＧＯＰの数を示す４ビットの情報である。
【０１１０】
Number_of_AUX_Data は、このレコーディングユニット内に含まれているAUX_Dataの数を示す８ビットの情報である。このNumber_of_AUX_Data は、ＧＯＰ毎に付加される。
【０１１１】
AUX_Data_Positionは、AUX_Layer内のどの位置からAUX_Dataの記録が開始されているかを示す３２ビットの情報である。
AUX_Data_byte_Lengthは、AUX_Dataのバイト数を示す３２ビットの情報である。
【０１１２】
AUX_Data_IDは、AUX_Dataの種類を示す８ビットのＩＤである。このAUX_Data_IDでは、ＶＩＴＣ、Ｖｉｄｅｏ Ｉｎｄｅｘ、Ｎｏｎ ＣｏｍｐｒｅｓｓｅｄＬｉｎｅ Ｄａｔａ、Ａｕｄｉｏ Ｃｈａｎｎｅｌ Ｓｔａｔｕｓ ｃｈ１／２、Ａｕｄｉｏ Ｃｈａｎｎｅｌ Ｓｔａｔｕｓ ｃｈ３／４を識別している。AUX_Data_PTS_Fieldは、AUX_Dataの出力タイミングを、レコーディングユニットの先頭からのフィールド数で示した８ビットの情報である。AUX_Data_PTS_Fieldは、このＭＰＥＧ−２データストリームとは別のストリームとして記録されるヘッダデータにのみ記録される。AUX_Data_Crcc_Flagは、AUX_Layer_HeaderのCrccコードが有効であるかを示す１ビットの情報である。Crccが無効である場合には“0”とし、Crccが有効である場合には“1”とする。AUX_32bitAlign_byte_Lengthは、補助データのバイト数を４の倍数にするために付加する２ビットの追加バイトである。AUX_Data_PTSは、補助データのＰＴＳを示す３３ビットの情報である。
【０１１３】
以上のAUX_Data_PositionからAUX_Data_PTSの情報は、補助データ単位で付加される。
【０１１４】
AUX_Layer_Header_Crccは、AUX_Layer_Header_の８ビットのCrccコードである。Crccは、AUX_Layer_Headerの先頭から１byte毎にAUX_Layer_header_byte_Length-1までを計算し、最後の１バイトのCrccコードを付加する。Crccが無効の場合は、“00h”とする。
【０１１５】
なお、AUX_VBI_Line_Flagは、AUX_Data_IDがＶｉｄｅｏ Ｉｎｄｅｘ又はＮｏｎ Ｃｏｍｐｒｅｓｓｅｄ Ｌｉｎｅ Ｄａｔａを示すとき、AUX_Data_PTSと入れ換える。３２ビットのデータのうちＬＳＢ側１６ビットで１ｓｔフィールドのＶｉｄｅｏ Ｉｎｄｅｘ Ｌｉｎｅ又はＮｏｎ Ｃｏｍｐｒｅｓｓｅｄ Ｌｉｎｅを指定する。また、３２ビットのデータのうちＭＳＢ側１６ビットで２ｎｄフィールドのＶｉｄｅｏ Ｉｎｄｅｘ Ｌｉｎｅ又はＮｏｎ Ｃｏｍｐｒｅｓｓｅｄ Ｌｉｎｅを指定する。ライン指定は、ＶＤの立ち上がりから、１６ラインの中から任意のラインを２バイトのデータで指定する。各ビットに１ラインを割り当てており、対応するビットに１を立てることにより、そのラインでＶｉｄｅｏ Ｉｎｄｅｘ Ｌｉｎｅ又はＮｏｎ Ｃｏｍｐｒｅｓｓｅｄ Ｌｉｎｅデータが挿入される。Ｖｉｄｅｏ Ｉｎｄｅｘ Ｌｉｎｅは、１Line/Fieldで指定可能であり、Ｎｏｎ Ｃｏｍｐｒｅｓｓｅｄ Ｌｉｎｅは、3Line/Fieldで指定可能である。
【０１１６】
各ビットとラインの関係は、以下の表に示すようになっている。
【０１１７】
【表２】

【０１１８】
【発明の効果】
本発明にかかるデータ記録再生装置及びデータ記録再生方法では、上記データとともに、このデータのヘッダ情報を記録媒体に記録しておき、上記記録媒体に記録した上記データを再生する際に、上記データのヘッダ情報を記録媒体から直接検出する。そして、本発明では、記録媒体に記録した上記データのヘッダ情報を、復号手段により復号する前に上記記録媒体から直接検出して、上記データの再生制御を行う。このため、本発明では、復号処理の負担を軽減させることができるともに再生処理を高速化することができる。
【図面の簡単な説明】
【図１】本発明を適用したデータ記録再生装置のブロック図である。
【図２】上記データ記録再生装置の記録時のデータ処理を説明するためのタイミングチャートである。
【図３】上記データ記録再生装置の再生時のデータ処理を説明するためのタイミングチャートである。
【図４】ＭＰＥＧ−２データの１ＧＯＰ分のデータ構造を説明するための図である。
【図５】 System_Layer_Headerのデータ構造を説明するための図である。
【図６】 Video_Layer_Headerのデータ構造を説明するための図である。
【図７】 Audio_Layer_Headerのデータ構造を説明するための図である。
【図８】 Audio_Layer_Headerのデータ構造を説明するための図である。
【図９】従来のデータ記録再生装置のブロック図である。
【図１０】上記従来のデータ記録再生装置の記録時のデータ処理を説明するためのタイミングチャートである。
【図１１】上記従来のデータ記録再生装置の再生時のデータ処理を説明するためのタイミングチャートである。
【符号の説明】
１ データ記録再生装置、２ 記録部、３ 再生部、４ ハードディスクドライブ、５ バス、６ コントローラ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data recording / reproducing apparatus and a data recording / reproducing method for recording / reproducing audio data and video data on / from a randomly accessible recording medium.
[0002]
[Prior art]
With the recent increase in capacity and price of hard disks and the like, a wide range of systems for recording video data, audio data, etc. on recording media such as hard disks that can be randomly accessed, instead of conventional VTRs (video tape recorders). It has come to be used. By recording video data and audio data on such a randomly accessible recording medium, for example, simultaneous recording, simultaneous reproduction, simultaneous recording and reproduction of a plurality of video data and the like are possible.
[0003]
FIG. 9 shows a conventional data recording / reproducing apparatus using a hard disk.
[0004]
A data recording / reproducing apparatus 100 shown in FIG. 9 is a so-called AV server that compresses video data and audio data and stores them in a hard disk.
[0005]
The data recording / reproducing apparatus 100 includes a recording unit 101, a reproducing unit 102, a hard disk drive 103 that stores video data and the like, and a bus 104 that performs data transmission between the recording unit 101, the reproducing unit 102, and the hard disk drive 103. A controller 105 for controlling the recording unit 101, the reproduction unit 102, and the hard disk drive 103.
[0006]
The data recording / reproducing apparatus 100 is supplied with verse band video data, baseband audio data, and auxiliary data in which auxiliary information of the input video data and audio data is described. The input video data and the like are encoded and recorded by the recording unit 101 and stored in the hard disk drive 103. Further, the data recording / reproducing apparatus 100 reads compressed video data and the like recorded in the hard disk drive 103, and the reproduction unit 102 performs decoding and reproduction processing of the video data and the like to obtain baseband video data and the like. Output. The controller 105 issues operation commands and the like, manages the processing timing of the recording unit 101 and the reproducing unit 102, the data transfer timing of the bus 104, the recording / reproducing timing of the hard disk drive 103, and the like, and controls the operation of each unit.
[0007]
The recording unit 101 includes a video data input terminal 111, an audio data input terminal 112, an auxiliary data input terminal 113, a video encoder 114, an audio encoder 115, an auxiliary data input processing unit 116, a video data memory 117, The audio data memory 118, the auxiliary data memory 119, and the recording side interface 120 are provided.
[0008]
Baseband video data is input to the video data input terminal 111. This baseband video data is supplied to the video encoder 114.
[0009]
Baseband audio data is input to the audio data input terminal 112. The baseband audio data is supplied to the audio encoder 115.
[0010]
Auxiliary data is input to the auxiliary data input terminal 113. This auxiliary data is supplied to the auxiliary data input processing unit 116.
[0011]
The video encoder 114 compresses the supplied baseband video data using the MPEG-2 method. The video elementary data subjected to image compression is supplied to the video data memory 117 in units of 1 GOP in accordance with a memory write command from the controller 105. Here, 1 GOP is an image processing unit defined by MPEG-2, and is generally composed of 15 frames in NTSC.
[0012]
  The audio encoder 115 converts the supplied baseband audio data intoMPEG systemCompress audio with. The audio elementary data subjected to audio compression is supplied to the audio data memory 118 in a data unit corresponding to 1 GOP as a processing unit of the video data in accordance with a memory write command from the controller 105.
[0013]
  The auxiliary data input processing unit 116 converts the supplied auxiliary data.RecordPerforms conversion processing to convert to format data. The auxiliary data subjected to the data conversion is supplied to the auxiliary data memory 119 in a data unit corresponding to 1 GOP as a processing unit of the video data in accordance with a memory write command from the controller 105.
[0014]
The video data memory 117 stores the supplied video elementary data in units of 1 GOP. The video data memory 117 supplies the stored video elementary data to the recording side interface 120 in units of 1 GOP according to a memory read command from the controller 105.
[0015]
The audio data memory 118 stores the supplied audio elementary data in units of 1 GOP. The audio data memory 118 supplies the stored audio elementary data to the recording side interface 120 in units of 1 GOP according to a memory read command from the controller 105.
[0016]
The auxiliary data memory 119 stores the supplied auxiliary data in units of 1 GOP. The auxiliary data memory 119 supplies the stored auxiliary data to the recording side interface 120 in units of 1 GOP in accordance with a memory read command from the controller 105.
[0017]
The recording-side interface 120 transfers video elementary data, audio elementary data, and auxiliary data for one GOP supplied from the video data memory 117, the audio data memory 118, and the auxiliary data memory 119 to the bus 104 such as a PCI format. The data format is converted in accordance with the protocol and transferred to the hard disk drive 103 via the bus 104.
[0018]
The hard disk drive 103 records the transferred video elementary data, audio elementary data, and auxiliary data in units of 1 GOP according to a recording command from the controller 105.
[0019]
The playback unit 102 includes a playback-side interface 121, a video data memory 122, an audio data memory 123, an auxiliary data memory 124, a video decoder 125, an audio decoder 126, an auxiliary data output processing unit 127, and a video output terminal. 128, an audio output terminal 129, and an auxiliary data output terminal 130.
[0020]
Video elementary data from the hard disk drive 103 reproduced in accordance with a reproduction command from the controller 105 is transferred to the reproduction side interface 121 via the bus 104. The transferred data is, for example, video elementary data, audio elementary data, and auxiliary data in a data format according to the transfer protocol of the bus 104 such as the PCI format, and is transferred in units of 1 GOP. The playback-side interface 121 converts the data format of the transferred data, and then separates it into three streams of video elementary data, audio elementary data, and auxiliary data. The separated video elementary data is supplied to the video data memory 122 in units of 1 GOP in accordance with a memory write command from the controller 105. The separated audio elementary data is supplied to the audio data memory 123 in units of 1 GOP in accordance with a memory write command from the controller 105. The separated auxiliary data is supplied to the auxiliary data memory 124 in units of 1 GOP according to a memory write command from the controller 105.
[0021]
The video data memory 122 stores the supplied video elementary data in units of 1 GOP. The video data memory 122 stores the stored video elementary data in the video decoder 125 in units of 1 GOP in accordance with a memory read command from the controller 105.
[0022]
The audio data memory 123 stores the supplied audio elementary data in units of 1 GOP. The audio data memory 123 supplies the stored audio elementary data to the audio encoder 126 in units of 1 GOP according to a memory read command from the controller 105.
[0023]
The auxiliary data memory 124 stores the supplied auxiliary data in units of 1 GOP. The auxiliary data memory 124 supplies the stored auxiliary data to the auxiliary data output processing unit 127 in units of 1 GOP according to the memory read command from the controller 105.
[0024]
The video decoder 125 decompresses the supplied video elementary data in units of 1 GOP in the MPEG-2 system. The video decoder 125 outputs baseband video data generated by image decompression from the video output terminal 128 to the outside in units of one frame.
[0025]
The audio decoder 126 decompresses the supplied audio elementary data in units of 1 GOP in the MPEG-2 system. The audio decoder 126 synchronizes the baseband audio data generated by audio decompression with the baseband video data output from the video output terminal 128, and outputs it from the audio output terminal 129.
[0026]
  The auxiliary data output processing unit 127RegenerationThe converted auxiliary data is converted into a data format that can be output. The auxiliary data output processing unit 127 outputs the auxiliary data whose data format has been converted from the auxiliary data output terminal 130 in synchronization with the baseband video data output from the video output terminal 128.
[0027]
In such a data recording / reproducing apparatus 100, data processing of each unit is performed at processing timings as shown in FIGS. FIG. 10 shows a timing chart of each process at the time of data recording, and FIG. 11 shows a timing chart of each process at the time of data reproduction.
[0028]
As shown in FIG. 10, the recording process includes a process until video data is input and encoding is completed, a process until encoded video data is written to and read from the video data memory 117, a bus The transfer process and the write process to the hard disk drive 103 are performed in units of 1 GOP, data is transferred for each 1 GOP, and the process proceeds to the next process. As for the audio data and auxiliary data, each process is performed in units corresponding to 1 GOP, similarly to the video data.
[0029]
Therefore, the input predetermined GOP (for example, GOP # 1 shown in FIG. 10) is recorded in the hard disk drive 103 at the processing timing after 3 GOP.
[0030]
As shown in FIG. 11, the reproduction process includes a read process from the hard disk drive 103, a bus transfer process, a process during which data transferred from the bus is written to and read from the video data memory 122, and a video data memory 122. The processing until the video data read out from is decoded and output is performed in units of 1 GOP, the data is transferred for each 1 GOP, and the process proceeds to the next processing. For audio data and auxiliary data, each process is performed in units corresponding to 1 GOP, similarly to video data.
[0031]
Accordingly, a predetermined GOP read from the hard disk drive 103 (for example, a GOP of # 11 shown in FIG. 11) is output at the processing timing after 3 GOP.
[0032]
[Problems to be solved by the invention]
By the way, in such a conventional data recording / reproducing apparatus 100, as shown in FIG. 11, before the video decoder 125 and the audio decoder 126 perform the decoding process, the PictureSize information and the Picture included in these data are stored in advance. Header data such as encoding pattern information and Audio Frame Size information must be detected from each stream. For this reason, the video decoder 125 and the audio decoder 126 have to perform both decoding processing of data for 1 GOP and detection processing of this header information within the processing time of 1 GOP. Therefore, in the conventional data recording / reproducing apparatus 100, the processing load of the video decoder 125 and the audio decoder 126 is large, and therefore the processing time of the entire apparatus cannot be increased. In addition, the auxiliary data input processing unit 127 must also perform post-processing after analyzing based on the header information of the auxiliary data what kind of data content information is included in the auxiliary data in advance. In time, both auxiliary information conversion processing and header information detection processing had to be performed.
[0033]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a data recording / reproducing apparatus and a data recording / reproducing method that reduce the processing of data decoding means during reproduction and increase the processing time. And
[0034]
[Means for Solving the Problems]
  In order to solve the above-described problems, a data recording / reproducing apparatus according to the present invention is provided with a recording medium, encoding means for inputting data including audio data and / or video data, and encoding the data; Recording means for recording the data encoded by the encoding means on the recording medium, reproducing means for reproducing the data recorded on the recording medium, and decoding the data reproduced by the reproducing means And decoding means for outputting the decoded data, and control means for controlling the encoding means, the recording means, the reproducing means, and the decoding means, and the control means comprises:When recording the data encoded by the encoding means on the recording medium by the recording means,The header information included in the data encoded by the encoding means is acquired, and the data including the header information is acquired.Data stream andObtained header informationStreamRecorded on the above recording mediumWhen reproducing the data stream from the recording medium, the header information obtained by reproducing the header information stream from the recording medium is analyzed, and the data stream is reproduced from the recording medium based on the analysis result. Control to decryptIt is characterized by that.
[0035]
  The present invention also includes a recording process in which data including audio data and / or video data is input, the data is encoded, and the encoded data is recorded on a recording medium, and the data is recorded on the recording medium. A data recording / reproducing method for reproducing the data, decoding the reproduced data, and outputting the decoded data, wherein the encoded data is recorded on the recording medium. The header information included in the encoded data is acquired, the data stream of the data including the header information and the acquired stream of header information are recorded on the recording medium, and When the data stream is reproduced from the recording medium, the header information obtained by reproducing the header information stream from the recording medium is analyzed, and the analysis result is analyzed. And performing control to decode and reproduce the data stream from the recording medium based on.
[0042]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0043]
FIG. 1 shows a data recording / reproducing apparatus to which the present invention is applied.
[0044]
A data recording / reproducing apparatus 1 shown in FIG. 1 is a so-called AV server that compresses video data and audio data and stores them in a hard disk.
[0045]
The data recording / reproducing apparatus 1 stores a recording unit 2 that performs encoding processing and recording processing of input video data, a playback unit 3 that performs decoding and playback processing of output video data, and video data. The hard disk drive 4 includes a bus 5 that transmits data between the recording unit 2 and the reproduction unit 3 and the hard disk drive 4, and a controller 6 that controls the recording unit 2, the reproduction unit 3, and the hard disk drive 4.
[0046]
The data recording / reproducing apparatus 1 receives verse band video data, baseband audio data, and auxiliary data in which auxiliary information of the input video data and audio data is described. The input video data and the like are encoded and recorded by the recording unit 2 and stored in the hard disk drive 4. The data recording / reproducing apparatus 1 also reads compressed video data and the like recorded on the hard disk drive 4, and the reproduction unit 3 performs decoding and reproduction processing of the video data and the like to obtain baseband video data and the like. Output. The controller 6 issues operation commands and the like, manages the processing timing of the recording unit 2 and the reproducing unit 3, the data transfer timing of the bus 5, the recording / reproducing timing of the hard disk drive 4, and the like, and controls the operation of each unit.
[0047]
The recording unit 2 includes a video data input terminal 11, an audio data input terminal 12, an auxiliary data input terminal 13, a video encoder 14, an audio encoder 15, an auxiliary data input processing unit 16, a video data memory 17, The audio data memory 18, the auxiliary data memory 19, the header data memory 20, and the recording side interface 21 are provided.
[0048]
Baseband video data is input to the video data input terminal 11. The baseband video data is supplied to the video encoder 14.
[0049]
Baseband audio data is input to the audio data input terminal 12. The baseband audio data is supplied to the audio encoder 15.
[0050]
The auxiliary data input terminal 13 receives auxiliary data indicating auxiliary information of input video data and audio data. This auxiliary data is supplied to the auxiliary data input processing unit 16.
[0051]
  The video encoder 14 compresses the supplied baseband video data using the MPEG-2 method. The video encoder 14 stores the compressed video elementary data without transferring 1 GOP, and supplies the stored video elementary data to the video data memory 17 in units of 1 GOP according to the memory write command from the controller 6. Note that 1 GOP is an image processing unit defined by MPEG-2.In NTSCIt consists of 15 frames.
[0052]
Here, the video elementary data supplied to the video data memory 17 includes header data. The video encoder 14 generates a stream describing the header data of the video elementary data different from the data stream of the video elementary data when generating the video elementary data compressed with the image. The video encoder 14 supplies this header data to the header data memory 20. Note that the header data supplied to the header data memory 20 is not limited to all the header data included in the video elementary data, but may include at least information necessary for reproduction.
[0053]
  The audio encoder 15 converts the supplied baseband audio data intoMPEG systemCompress audio with. The audio encoder 15 supplies audio-compressed audio elementary data to the audio data memory 18 in units of data corresponding to 1 GOP as a processing unit of the video data in accordance with a memory write command from the controller 6.
[0054]
Here, the audio elementary data supplied to the audio data memory 18 includes header data. When the audio encoder 15 generates audio elementary data that has been subjected to voice compression, the audio encoder 15 generates a stream in which header data of the audio elementary data is described, which is different from the data stream of the audio elementary data. The audio encoder 15 supplies this header data to the header data memory 20. It should be noted that the header data of the audio elementary data supplied to the header data memory 20 is not limited to all the header data included in the audio elementary data, but may include at least information necessary for reproduction.
[0055]
  The auxiliary data input processing unit 16 receives the supplied auxiliary data.RecordPerforms conversion processing to convert to format data. The auxiliary data input processing unit 16 supplies the auxiliary data subjected to the data conversion to the auxiliary data memory 19 in accordance with a memory write command from the controller 6 in a data unit corresponding to 1 GOP of the video data processing unit.
[0056]
Here, the auxiliary data supplied to the auxiliary data memory 19 includes header data. When the auxiliary data input processing unit 16 converts the data format of the auxiliary data to the MPEG-2 system, the auxiliary data input processing unit 16 generates a stream describing the header information of the auxiliary data, which is different from the data stream of the auxiliary data. The auxiliary data input processing unit 16 supplies this header data to the header data memory 20. Note that the header data of the auxiliary data supplied to the header data memory 20 is not limited to all the header data included in the auxiliary data, but may include at least information necessary for reproduction.
[0057]
  Here, the auxiliary data supplied to the auxiliary data memory 19 includes header data. The auxiliary data input processing unit 16 changes the data format of the auxiliary data.Data format to recordWhen converting to the above, a stream in which header information of the auxiliary data is described, which is different from the data stream of the auxiliary data, is generated. The auxiliary data input processing unit 16 supplies this header data to the header data memory 20. Note that the header data of the auxiliary data supplied to the header data memory 20 is not limited to all the header data included in the auxiliary data, but may include at least information necessary for reproduction.
[0058]
The audio data memory 18 stores the supplied audio elementary data in units of 1 GOP. The audio data memory 18 supplies the stored audio elementary data to the recording side interface 21 in units of 1 GOP in accordance with a memory read command from the controller 6.
[0059]
The auxiliary data memory 19 stores the supplied auxiliary data in units of 1 GOP. The auxiliary data memory 19 supplies the stored auxiliary data to the recording side interface 21 in units of 1 GOP according to the memory read command from the controller 6.
[0060]
  The header data memory 20 stores each supplied header data in units of 1 GOP. The header data memory 20 supplies the stored header data to the recording side interface 21 in units of 1 GOP in accordance with a memory read command from the controller 6. The header data stored in the header data memory 20 includes, for example, information such as Picture Size, Picture Coding Type, Profile, Level, etc. of each picture necessary for reproduction, and each audio frame.frame There are information such as Size, sampling frequency, and emphasis, and information such as Data Size and ID of auxiliary data.
[0061]
The recording-side interface 21 receives video elementary data, audio elementary data, auxiliary data, and header data for one GOP supplied from the video data memory 17, audio data memory 18, auxiliary data memory 19 and header data memory 20, for example, The data is converted into a data format according to a transfer protocol of the bus 5 such as a PCI format, and transferred to the hard disk drive 4 via the bus 5.
[0062]
The hard disk drive 4 records the transferred video elementary data, audio elementary data, auxiliary data, and header data in units of 1 GOP according to the recording command from the controller 6.
[0063]
The playback unit 3 includes a playback-side interface 31, a video data memory 32, an audio data memory 33, an auxiliary data memory 34, a header data memory 35, a video decoder 36, an audio decoder 37, and an auxiliary data output processing unit. 38, a video output terminal 39, an audio output terminal 40, and an auxiliary data output terminal 41.
[0064]
Video elementary data from the hard disk drive 4 reproduced in accordance with a reproduction command from the controller 6 is transferred to the reproduction side interface 31 via the bus 5. The data to be transferred is video elementary data, audio elementary data, auxiliary data, and header data in a data format according to the transfer protocol of the bus 5 such as the PCI format, and is transferred in units of 1 GOP. . The playback-side interface 31 converts the data format of these transferred data, and then separates the data into three data streams: video elementary data, audio elementary data, auxiliary data, and header data.
[0065]
Of the separated data, first, header data is supplied from the reproduction-side interface 31 to the header memory 35. Here, the controller 6 reads out data size information of video elementary data, audio elementary data, and auxiliary data from the header data stored in the header memory 35. The controller 6 issues a memory write command, which is a processing instruction for writing data having a data amount of 1 GOP from the playback-side interface 31 to each of the memories 32 to 34 based on the data size information of each data. The playback-side interface 31 supplies the separated video elementary data to the video data memory 32 in units of 1 GOP according to the memory write command from the controller 6. Further, the playback-side interface 31 supplies the separated audio elementary data to the audio data memory 33 in units of 1 GOP according to the memory write command from the controller 6. The playback-side interface 31 supplies the separated auxiliary data to the auxiliary data memory 34 in units of 1 GOP according to the memory write command from the controller 6.
[0066]
  When the header data is stored in the header data memory 35, the controller 6 reads out all the header data stored in the header memory 35 and analyzes the header data. Then, the controller 6 receives information necessary for decoding and reproduction of the video data obtained as a result of analyzing the header data, for example, information such as Picture Size, Picture Coding Type, Profile, Level, and the like of each picture. To supply. The controller 6 also provides information necessary for decoding the audio data obtained as a result of analyzing the header data, for example, each audio frame.frame Information such as Size, sampling frequency, and emphasis is supplied to the audio decoder 37. Further, the controller 6 supplies the auxiliary data output processing unit 38 with information necessary for changing the auxiliary data obtained as a result of analyzing the header information, for example, information such as Data Size and ID of the auxiliary data.
[0067]
The video data memory 32 stores the supplied video elementary data in units of 1 GOP. The video data memory 32 stores the stored video elementary data in the video decoder 36 in units of 1 GOP in accordance with a memory read command from the controller 6.
[0068]
The audio data memory 33 stores the supplied audio elementary data in units of 1 GOP. The audio data memory 33 supplies the stored audio elementary data to the audio encoder 37 in units of 1 GOP in accordance with a memory read command from the controller 6.
[0069]
The auxiliary data memory 34 stores the supplied auxiliary data in units of 1 GOP. The auxiliary data memory 34 supplies the stored auxiliary data to the auxiliary data output processing unit 38 in units of 1 GOP in accordance with a memory read command from the controller 6.
[0070]
The header data memory 35 stores the supplied header data. The header data memory 34 supplies this header data to the controller 6. The header data memory 34 supplies each header data to the video decoder 36, the audio decoder 37, or the auxiliary data output processing unit 38 in accordance with a memory read command from the controller 6.
[0071]
The video decoder 36 decompresses the supplied video elementary data in units of 1 GOP in the MPEG-2 system. The video decoder 36 outputs the baseband video data generated by image expansion to the outside from the video output terminal 39 in units of one frame. At this time, the video decoder 36 does not analyze the header data included in the video elementary data supplied from the video data memory 32, and performs a decoding process based on the information supplied from the controller 6. Therefore, the video decoder 36 does not need to perform header data analysis processing, the decoding processing is reduced, and the speed of the decoding processing can be increased.
[0072]
  The audio decoder 37 receives the supplied audio elementary data.MPEG systemThe voice is expanded by 1 GOP. The audio decoder 37 outputs the baseband audio data generated by the audio expansion from the audio output terminal 40 in synchronization with the baseband video data output from the video output terminal 39. At this time, the audio decoder 37 does not analyze the header data included in the audio elementary data supplied from the audio data memory 33, and performs a decoding process based on the information supplied from the controller 6. Therefore, the audio decoder 37 does not have to perform header data analysis processing, the decoding processing is reduced, and the speed of the decoding processing can be increased.
[0073]
  The auxiliary data output processing unit 38RegenerationThe converted auxiliary data is converted into a data format that can be output. The auxiliary data output processing unit 38 outputs the auxiliary data whose data format has been converted from the auxiliary data output terminal 41 in synchronization with the baseband video data output from the video output terminal 39. At this time, the auxiliary data output processing unit 38 does not analyze the header data included in the auxiliary data supplied from the auxiliary data memory 34, and performs the conversion process based on the information supplied from the controller 6. Therefore, the auxiliary data output processing unit 38 does not need to perform header data analysis processing, the conversion processing is reduced, and the conversion processing can be speeded up.
[0074]
In such a data recording / reproducing apparatus 1, data processing of each unit is performed at processing timings as shown in FIGS. FIG. 2 shows a timing chart of each process at the time of data recording, and FIG. 3 shows a timing chart of each process at the time of data reproduction.
[0075]
As shown in FIG. 2, the recording process includes a process until video data is input and encoding is completed, a process until encoded video data is written to and read from the video data memory 17, and a bus The transfer process and the write process to the hard disk drive 4 are performed in units of 1 GOP, the data transfer is performed for each 1 GOP, and the process proceeds to the next process. As for the audio data and auxiliary data, each process is performed in units corresponding to 1 GOP, similarly to the video data.
[0076]
Accordingly, the input predetermined GOP (for example, GOP # 1 shown in FIG. 2) is recorded in the hard disk drive 4 at the processing timing after 3 GOP.
[0077]
Here, in the recording process, header data included in video elementary data or the like generated at the time of encoding is transferred to the header data memory 20. The header data transferred to the header data memory 20 is transferred to the hard disk drive 4 through the bus 5 together with the video elementary data, audio elementary data, and auxiliary data at the time of bus transfer. The hard disk drive 4 records the transferred header data together with the video elementary data and the like.
[0078]
As shown in FIG. 3, the reproduction process includes a read process from the hard disk drive 4, a bus transfer process, a process during which data transferred from the bus is written to and read from the video data memory 32, and the video data memory 32. The processing until the video data read out from is decoded and output is performed in units of 1 GOP, the data is transferred for each 1 GOP, and the process proceeds to the next processing. For audio data and auxiliary data, each process is performed in units corresponding to 1 GOP, similarly to video data.
[0079]
Therefore, a predetermined GOP read from the hard disk drive 4 (for example, G11 of # 11 shown in FIG. 3) is output at the processing timing after 3 GOP.
[0080]
In the reproduction process, the header data is written into the header data memory 35 prior to the writing of the video elementary data or the like at the time of memory writing. When this header data is written in the header data memory 35, the controller 6 starts analyzing the header data. Therefore, the analysis is not performed after the data is supplied to the video decoder 36 as in the prior art, but the controller 6 analyzes the header data at least one GOP or more before. Therefore, at the time of reproduction, it is possible to reduce the processing load at the time of decoding and to speed up the processing at the time of decoding.
[0081]
As described above, in the data recording / reproducing apparatus 1 to which the present invention is applied, the header information included in the video elementary data or the like is stored in the hard disk drive 4 when the compressed video elementary data or the like is recorded on the hard disk drive 4. Record in drive 4. During playback, header data such as video elementary data recorded in the hard disk drive 4 is directly detected from the hard disk drive 4 and playback control of the video elementary data and the like is performed. Therefore, in the data recording / reproducing apparatus 1, it is possible to reduce the burden of the decoding process and to speed up the reproduction process.
[0082]
Next, specific data contents of the header data recorded on the hard disk drive 4 will be described. The following data example is for the case of Number_of_GOP = 1, Number_of_Picture = 15, Number_of_AFRAME = 21, Number_of_Audio_Stereo_Channel = 2, Number_of_AUX_Data = 4.
[0083]
FIG. 4 shows the data structure of 1 GOP of MPEG-2 data.
[0084]
As shown in FIG. 4, MPEG-2 data for 1 GOP includes System_Layer_Header, Video_Layer_Header, Video_Stream_byte, Audio_1 / 2ch_Layer_Header, Audio_1 / 2ch_Layer_byte, Audio_3 / 4ch_Layer_Header, Audio_3 / 4ch_Layer_byte, AUX_Layer_Header, Consists of AUX_Date_byte.
[0085]
System_Layer_Header is 128-byte information, and is header information that controls all data in one GOP. Video_Layer_Header is 376-byte information and is header information of video data. Video_Stream_byte is video elementary data for 1 GOP. Audio_1 / 2ch_Layer_Header is 104-byte information and is header information of one of the two audio data. Audio_1 / 2ch_Layer_byte is audio elementary data of one of the two audio data. Audio_3 / 4ch_Layer_Header is 104-byte information, and is header information of the other audio data of the two audio data. Audio_3 / 4ch_Layer_byte is the other audio elementary data of the two audio data. AUX_Layer_Header is 76-byte information and is header information of auxiliary data. AUX_Date_byte is auxiliary data.
[0086]
In addition to the data stream having the above data structure, the hard disk drive 4 records a header data stream in which System_Layer_Header, Video_Layer_Header, Audio_1 / 2ch_Layer_Header, Audio_3 / 4ch_Layer_Header, and AUX_Layer_Header described different from this data stream are recorded.
[0087]
Hereinafter, the data structure of header data recorded as a stream different from the MPEG-2 data stream will be described.
[0088]
First, the contents of System_Layer_Header will be described. FIG. 5 shows the data structure of System_Layer_Header.
[0089]
Wing_Header_ID is 56-bit ID data indicating Wing Data. The ASCII code is described as “Wing_ID”.
Header_Version_ID is 8-bit ID data representing the version of the header data.
System_Layer_Header_byte_Length is 32-bit information indicating the number of bytes of System_Layer_Header.
Video_Layer_Header_Position is 32-bit information indicating from which position in this recording unit the Video_Layer_Header starts, and indicates the number of bytes from the beginning of this recording unit.
[0090]
Audio_1 / 2ch_Layer_Header_Position is 32-bit information indicating from which position in the recording unit the Audio_1 / 2ch_Layer_Header starts, and indicates the number of bytes from the beginning of the recording unit. If the data is 0, the channel is not recorded.
Audio_3 / 4ch_Layer_Header_Position is 32-bit information indicating from which position in the recording unit the Audio_3 / 4ch_Layer_Header starts, and indicates the number of bytes from the beginning of the recording unit. If the data is 0, the channel is not recorded.
Audio_5 / 6ch_Layer_Header_Position is 32-bit information indicating from which position in the recording unit the Audio_5 / 6ch_Layer_Header starts, and indicates the number of bytes from the beginning of the recording unit. If the data is 0, the channel is not recorded.
Audio_7 / 8ch_Layer_Header_Position is 32-bit information indicating from which position in the recording unit the Audio_7 / 8ch_Layer_Header starts, and indicates the number of bytes from the beginning of the recording unit. If the data is 0, the channel is not recorded.
[0091]
The above Audio_n / mch_Layer_Header_Position is recorded only in header data recorded as a stream different from this MPEG-2 data stream.
[0092]
AUX_Layer_Header_Position is 32-bit information indicating from which position in this recording unit the AUX_Layer_Header starts, and indicates the number of bytes from the beginning of this recording unit.
Recording_Unit_byte_Length is 32-bit information indicating the number of bytes of this recording unit.
Number_of_Recording_Unit_Field is 8-bit information representing the time required for reproduction of this recording unit in field units. For example, when there is 2-3 pull-down, it is provided because the playback time is different even if 1 GOP is 15 frames.
Recording_Unit_Closed_Flag is information indicating whether the first GOP of this recording unit is a closed GOP. If it is a closed GOP, playback is possible from the beginning of this recording unit. If it is not a closed GOP, it must be played from the previous recording unit. Error_Flag is information indicating whether an error exists in the recording unit. Set to “0” if there is no error, and “1” if there is an error. This Error_Flag is recorded only in header data recorded as a stream different from this MPEG-2 data stream. Crash_Flag is information indicating whether or not the recording unit has been completely extracted. Set to “0” if the complete form can be taken out, and “1” if the full form cannot be taken out. Recording_Unit_Closed_Flag, Error_Flag, and Crash_Flag form a total of 8-bit data.
Crcc_Flag_Mode is 3-bit information indicating a mode for adding Crcc. When 3 bits MSB is b2 and LSB is b0, when b0 = 1, Crcc is added at the end of each Picture_Stream, when b1 =, Crcc is added at the end of each Audio_Frame_Stream, and when B2 = 1, the end of each AUX_Data_byte Add Crcc.
System_Layer_Header_Crcc_Flag is 1-bit information indicating whether Crcc of System_Layer_Header is valid. Set to “0” when Crcc is invalid and “1” when Crcc is valid.
GOP_ID is 32-bit information indicating the GOP number from the start of recording. If it is a recording start GOP, “0001h” is set.
Scanning_System_Flag is 8-bit information indicating the number of lines, field frequency, and aspect ratio. The contents indicated by the 8-bit data of Scanning_System_Flag are as follows.
“00000000” No information “00000001” 525 / 59.94 / 4x3 “00000010” 626/50 / 4x3 “00000011” Reserved “00000100” Reserved “00000101” 525 / 59.94 / 16x9 “00000110” 625/50 / 16x9 “00000111” to “ 11111111 ”Reserved
mark_bit is a spare bit.
System_Layer_Header_Crcc is an 8-bit Crcc code of System_Layer_Header_. Crcc calculates System_Layer_header_byte_Length-1 for each byte from the beginning of System_Layer_Header, and adds a 1-byte Crcc code at the end. If Crcc is disabled, set to “00h”.
[0093]
Next, the contents of Video_Layer_Header will be described. FIG. 6 shows the data structure of Video_Layer_Header.
[0094]
Video_Layer_Header_byte_Length is 16-bit information indicating the number of bytes of Video_Layer_Header.
Video_Layer_Header_Crcc_Flag is 1-bit information indicating whether the Crcc code of Video_Layer_Header is valid. Set to “0” when Crcc is invalid and “1” when Crcc is valid.
Video_Vertical_Size_Flag is 2-bit information indicating the number of pixels in the vertical direction of the image. “00” indicates 480 pixels, “01” indicates 512 pixels, “10” indicates 240 pixels, and “11” is reserved.
Video_Horizontal_Size_Flag is 2-bit information indicating the number of pixels in the horizontal direction of the image. “00” indicates 720 pixels, “01” indicates 544 pixels, “10” indicates 480 pixels, and “11” indicates 352 pixels.
Video_Profile_Level_Flag is 4-bit information indicating Profile and Level.
“0000” indicates MP @ ML, and “0001” indicates 422 @ ML.
Video_Source_Composite_Flag is 1-bit information indicating whether the source of video data is a composite signal. “1” indicates that the source is a composite signal, and “0” indicates that the source is a component signal.
Video_Source_Analog_Flag is 1-bit information indicating whether the source of video data is an analog signal. “1” indicates that the source is an analog signal, and “0” indicates that the source is a digital signal.
Number_of_GOP is 4-bit information indicating the number of GOPs included in the recording unit.
Video_Coding_Rate is 32-bit information indicating the bit rate of the video elementary data stream.
[0095]
Sequence_Header_Flag is 1-bit information indicating whether or not a sequence header exists at the head of the GOP. If there is no sequence header at the beginning of the GOP, the video decoder cannot accurately decode the video data.
Sequence_End_Flag is 1-bit information indicating whether a sequence end code is present in the GOP.
Number_of_picture is 4-bit information indicating the number of pictures included in the GOP.
Note that the above Sequence_Header_Flag, Sequence_End_Flag, and Number_of_picture are information added in GOP units.
[0096]
Picture_Stream_byte_Length is information indicating the number of bytes of picture data. Specifically, it is 32-bit information indicating the length from Sequence_start_code, group_start_code or picture_start_code to the next Sequence_start_code, group_start_code or picture_start_code.
Picture_Crcc_Flag is 1-bit information indicating whether a Crcc code is attached to each picture. Crcc calculates up to Picture_Stream_byte_Length for each byte from the beginning of the picture, and adds a 1-byte Crcc code at the end. If Crcc is disabled, set to “00h”.
Picture_32bitAlign_byte_Length is a 2-bit additional byte added to make the number of bytes of picture data a multiple of four.
Picture_Coding_Type is information indicating the coding structure of a picture. The 3-bit data of Picture_Coding_Type indicates the following contents.
“000” forbidden “001” intra-coded (I) “010” predictive-coded (P) “011” bidirectionally-predictive-coded (B) “100” shall not be used (dc intra-coded (D)) “ 101 ”reserved“ 110 ”reserved“ 111 ”reserved
PTS_Field is 8-bit information that represents the output timing of a picture as the number of fields from the first picture of the recording unit. PTS_Field is recorded only in header data recorded as a stream different from the MPEG-2 data stream.
PTS is 33-bit information indicating PTS (Presentation Time Stamp) of each picture. PTS represents the output time of a picture with 90 kHz accuracy.
Color_Frame is 3-bit information representing a color frame. When the picture is a frame, the color frame of the first field is recorded. When the 3-bit MSB is b2 and the LSB is b0, b0 indicates color frame 0, b1 indicates color frame 1, and b2 indicates color frame 2.
DTS_Field is 8-bit information representing the picture decoding timing as the number of fields from the first picture of the recording unit. The DTS_Field is recorded only in header data recorded as a stream different from the MPEG-2 data stream.
The DTS is 33-bit information indicating a DTS (Decoding Time Stamp) of each picture. The DTS represents a picture decoding time with 90 kHz accuracy.
VBV_Occupancy is 32-bit information indicating the number of bytes of the VBV buffer immediately before data extraction of the virtual decoder.
The above information from Picture_Stream_byte_Length to VBV_Occupancy is information repeatedly added for each picture.
[0097]
Video_Layer_Header_Crcc is an 8-bit Crcc code of Video_Layer_Header_. Crcc calculates Video_Layer_header_byte_Length-1 for each byte from the beginning of Video_Layer_Header, and adds the last 1-byte Crcc code. If Crcc is disabled, set to “00h”.
[0098]
Next, the contents of Audio_Layer_Header will be described. FIG. 7 shows the data structure of Audio_Layer_Header. When there are a plurality of audio data, this Audio_Layer_Header is provided for the number of channels.
[0099]
Audio_Layer_Header_byte_Length is 16-bit information indicating the number of bytes of Audio_Layer_Header.
Audio_Layer_Header_Crcc_Flag is 1-bit information indicating whether the Crcc code of Audio_Layer_Header is valid. Set to “0” when Crcc is invalid and “1” when Crcc is valid.
FS is 2-bit information indicating the sampling frequency of audio data. When the sampling frequency is 44.1 kHz, it is “00”, when it is 48 kHz, it is “01”, and when it is 32 kHz, it is “10”. “11” is reserved.
Audio_Emphasis_Flag is 1-bit information indicating audio emphasis. “0” indicates OFF, and “1” indicates ON.
Audio_Coding_Rate is 4-bit information indicating the bit rate of the compressed audio data. Specifically, the 4-bit information of Audio_Coding_Rate represents the following bit rate.
[0100]
[Table 1]

[0101]
Audio_Validity_Flag is 1-bit information indicating “0” when the audio data is valid and indicating “1” when the audio data is invalid.
Audio_Source_Analog_Flag is 1-bit information indicating whether the source of audio data is an analog signal. Set to “1” if the source is an analog signal and “0” if the source is a digital signal.
Duplicate_Flag is 2-bit information indicating whether or not data (margin data) overlapping with other recording units is included in the beginning or end of this recording unit. Set to “00” when there is no margin data, “01” when margin data is included at the beginning, and “10” when margin data is included at the end. When margin data is included in the beginning and end parts, “11” is set.
Number_of_GOP is 4-bit information indicating the number of GOPs included in this recording unit.
Number_of_Audio_Quantization_Bit is 4-bit information indicating a quantization bit of audio data. Specifically, Number_of_Audio_Quantization_Bit indicates the following information.
“0000” indicates that the quantization bit is 16 bits, “0001” is 17 bits, “0010” is 18 bits, “0011” is 19 bits, “0100” is 20 bits, “0101” is 21 bits, “0110” indicates 22 bits, “0111” indicates 23 bits, “1000” indicates 24 bits, and the others indicate reserve.
Audio_Coding_Flag is 2-bit information indicating encoding information of audio data. Set to “00” for MPEG Audio Layer II and “01” for Linear PCM.
mark_bit is a spare bit.
[0102]
Number_of_Audio_Frame is 5-bit information indicating the number of audio frames included in the GOP. It also includes audio frames that contain margin data.
PTS_FS is 11-bit information that represents the output timing of an audio frame as a relative phase to the video reference frame. PTS_FS is recorded only in header data recorded as a stream different from the MPEG-2 data stream.
Audio_PTS is 33-bit information indicating a PTS (Presentation Time Stamp) of each audio frame. PTS represents the output time of an audio frame with 90 kHz accuracy.
The above Number_of_Audio_Frame, PTS_FS, and Audio_PTS are information added in units of GOP.
[0103]
Audio_Frame_Stream_byte_Length is 16-bit information indicating the number of bytes of audio data.
[0104]
Audio_Frame_Crcc_Flag is 1-bit information indicating whether the Crcc code is valid for each audio frame.
[0105]
Audio_32bitAlign_byte_Length is a 2-bit additional byte added to make the number of bytes of audio data a multiple of four.
Edit_Flag is information indicating that the audio frame has been edited. “00” indicates that editing has not been performed, “01” indicates that it is an in point, “10” indicates that it is an out point, and “11” indicates reserve.
[0106]
The above information from Audio_Frame_Stream_byte_Length to Edit_Flag is information added for each audio frame.
[0107]
Audio_Layer_Header_Crcc is a Crcc code of 8-bit Audio_Layer_Header_. Crcc calculates Audio_Layer_header_byte_Length-1 for each byte from the beginning of Audio_Layer_Header, and adds a 1-byte Crcc code at the end. If Crcc is disabled, set to “00h”.
[0108]
Next, the contents of AUX_Layer_Header will be described. FIG. 8 shows the data structure of Audio_Layer_Header.
[0109]
AUX_Layer_Header_byte_Length is 16-bit information indicating the number of bytes of AUX_Layer_Header.
AUX_Layer_Header_Crcc_Flag is 1-bit information indicating whether or not the AUX_Layer_Header Crcc code is valid.
Number_of_GOP is 4-bit information indicating the number of GOPs included in this recording unit.
[0110]
Number_of_AUX_Data is 8-bit information indicating the number of AUX_Data included in this recording unit. This Number_of_AUX_Data is added for each GOP.
[0111]
AUX_Data_Position is 32-bit information indicating from which position in the AUX_Layer recording of AUX_Data is started.
AUX_Data_byte_Length is 32-bit information indicating the number of bytes of AUX_Data.
[0112]
  AUX_Data_ID is an 8-bit ID indicating the type of AUX_Data. In this AUX_Data_ID, VITC, Video Index, Non Compressed Line Data, Audio Channel Status ch1 / 2, Audio Channel Statusch3 / 4Has been identified. AUX_Data_PTS_Field is 8-bit information indicating the output timing of AUX_Data by the number of fields from the beginning of the recording unit. AUX_Data_PTS_Field is recorded only in header data recorded as a stream different from this MPEG-2 data stream. AUX_Data_Crcc_Flag is 1-bit information indicating whether or not the AUX_Layer_Header Crcc code is valid. Set to “0” when Crcc is invalid and “1” when Crcc is valid. AUX_32bitAlign_byte_Length is a 2-bit additional byte added to make the number of bytes of auxiliary data a multiple of 4. AUX_Data_PTS is 33-bit information indicating the PTS of the auxiliary data.
[0113]
The information from AUX_Data_Position to AUX_Data_PTS is added in units of auxiliary data.
[0114]
AUX_Layer_Header_Crcc is an 8-bit Crcc code of AUX_Layer_Header_. Crcc calculates AUX_Layer_header_byte_Length-1 every 1 byte from the beginning of AUX_Layer_Header, and adds the last one byte of Crcc code. If Crcc is disabled, set to “00h”.
[0115]
AUX_VBI_Line_Flag is replaced with AUX_Data_PTS when AUX_Data_ID indicates Video Index or Non Compressed Line Data. The Video Index Line or Non Compressed Line of the 1st field is designated by 16 bits on the LSB side of the 32-bit data. Also, the Video Index Line or Non Compressed Line of the 2nd field is designated by 16 bits of the MSB side of the 32-bit data. Line designation designates an arbitrary line from 16 lines with the data of 2 bytes from the rising edge of VD. One line is assigned to each bit, and by setting 1 to the corresponding bit, Video Index Line or Non Compressed Line data is inserted in that line. The Video Index Line can be specified by 1 Line / Field, and the Non Compressed Line can be specified by 3 Line / Field.
[0116]
The relationship between each bit and line is as shown in the following table.
[0117]
[Table 2]

[0118]
【The invention's effect】
In the data recording / reproducing apparatus and the data recording / reproducing method according to the present invention, the header information of the data is recorded on a recording medium together with the data, and when the data recorded on the recording medium is reproduced, The header information is detected directly from the recording medium. In the present invention, the header information of the data recorded on the recording medium is directly detected from the recording medium before being decoded by the decoding means, and reproduction control of the data is performed. For this reason, in the present invention, it is possible to reduce the load of the decoding process and to speed up the reproduction process.
[Brief description of the drawings]
FIG. 1 is a block diagram of a data recording / reproducing apparatus to which the present invention is applied.
FIG. 2 is a timing chart for explaining data processing during recording by the data recording / reproducing apparatus.
FIG. 3 is a timing chart for explaining data processing during reproduction by the data recording / reproducing apparatus.
FIG. 4 is a diagram for explaining a data structure of one GOP of MPEG-2 data.
FIG. 5 is a diagram for explaining a data structure of System_Layer_Header.
FIG. 6 is a diagram for explaining the data structure of Video_Layer_Header.
FIG. 7 is a diagram for explaining the data structure of Audio_Layer_Header.
FIG. 8 is a diagram for explaining the data structure of Audio_Layer_Header.
FIG. 9 is a block diagram of a conventional data recording / reproducing apparatus.
FIG. 10 is a timing chart for explaining data processing at the time of recording in the conventional data recording / reproducing apparatus.
FIG. 11 is a timing chart for explaining data processing during reproduction of the conventional data recording / reproducing apparatus.
[Explanation of symbols]
1 data recording / reproducing apparatus, 2 recording unit, 3 reproducing unit, 4 hard disk drive, 5 bus, 6 controller

Claims (2)

A recording medium, encoding means for inputting data including audio data and / or video data, and encoding the data;
Recording means for recording the data encoded by the encoding means on the recording medium;
Reproducing means for reproducing the data recorded on the recording medium;
Decoding means for decoding the data reproduced by the reproduction means and outputting the decoded data;
Control means for controlling the encoding means, the recording means, the reproducing means, and the decoding means,
The control unit obtains header information included in the data encoded by the encoding unit when the data encoded by the encoding unit is recorded on the recording medium by the recording unit. Te, when a data stream of the data which the header information is included, the stream of acquired the header information recorded on the recording medium, and reproduces the data stream from the recording medium, the header information from the recording medium A data recording / reproducing apparatus for analyzing the header information obtained by reproducing the stream, and reproducing and decoding the data stream from the recording medium based on the analysis result . Inputting data including audio data and / or video data, encoding the data, recording the encoded data on a recording medium, and reproducing the data recorded on the recording medium; A data recording / reproducing method for decoding the reproduced data and performing reproduction processing for outputting the decoded data,
When the encoded data is recorded on the recording medium, the header information included in the encoded data is acquired, and the data stream of the data including the header information is acquired. Record the header information stream on the recording medium ,
When reproducing the data stream from the recording medium, the header information obtained by reproducing the header information stream from the recording medium is analyzed, and the data stream is reproduced from the recording medium and decoded based on the analysis result. A data recording / reproducing method characterized in that control is performed .

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