Artifacts to ACM MMSys'20 paper "Comparing fixed and variable segment durations for adaptive video streaming: a holistic analysis". Available here

Docker container for DASH video encoding using FFMPEG.

The following parameters can be specified:

• video: input video
• reference_video: reference video for quality calculation
• crf: target output quality
• min_length: minimum duration of a segment in seconds (relevant in case of variable segment duration encoding)
• max_length: maximum duration of a segment in seconds (relevant in case of variable segment duration encoding)
• target_seg_length: fix duration in seconds of all video segments (in case of variable set target_seg_length=0.0)
• encoder: encoder. supported: x264. planned to be supported: x265, vp9
• timestamps: I-frame positions from reference encoding
• cst_bitrate: target bitrate for constant bitrate encoding (cbr)

If the source video shall be splitted into segments of fixed duration, set maxdur=mindur=target_seg_length=[fix duration]; If the source video shall be splitted into segments of variable duration, please set target_seg_length=0.0. You can find example job files under samples/jobs/00_waiting/.

• Docker
• Python

Additional Requirements:

• Linux OS
• wget
• screen

Steps 2, 3 and 4 are optional and can be skipped, if only example files should be used.

1. Run init_mmsys.sh
2. Create Job Files as described here.
3. Copy them into jobs/00_waiting/.
4. Copy the source videos into videos/.
5. Run run_workers_mmsys.sh.
6. Video statistics file are located at results/ and encoded videos at sshfs_dir/.

Different examples:

• bigbuckbunny480p24x30s_var_vbr_job001.txt: Variable Length VBR encoding
• bigbuckbunny480p24x30s_var_cbr_job002.txt: Variable Length CBR encoding
• bigbuckbunny480p24x30s_fix_vbr_job003.txt: Fixed Length VBR encoding
• bigbuckbunny480p24x30s_fix_cbr_job004.txt: Fixed Length CBR encoding

template-file: bigbuckbunny480p24x30s_var_vbr_job001.txt

ffmpeg -i /videos/bigbuckbunny480p24x30s.y4m -nostats -map 0:0 -threads 1 -vcodec libx264 -crf 16 -x264-params keyint=0:min-keyint=96:scenecut=-1 -force_key_frames 0.0,1.0,2.0 -use_timeline 1 -use_template 1 -hls_playlist 1 -seg_duration 0  -use_timeline 1 -f dash /tmpdir/crf_16.mpd

template-file: bigbuckbunny480p24x30s_var_cbr_job002.txt

ffmpeg -i /videos/bigbuckbunny480p24x30s.y4m -nostats -map 0:0 -threads 1 -vcodec libx264 -crf 16 -x264-params keyint=0:min-keyint=96:scenecut=-1 -force_key_frames 123456 -use_timeline 1 -use_template 1 -hls_playlist 1 -seg_duration 0  -use_timeline 1 -f dash /tmpdir/crf_16.mpd

template-file: bigbuckbunny480p24x30s_fix_cbr_job004.txt

ffmpeg -i /videos/bigbuckbunny480p24x30s.y4m -nostats -threads 1 -map 0:0 -vcodec libx264 -x264-params keyint=96:min-keyint=96 -use_timeline 0 -use_template 0 -hls_playlist 1 -seg_duration 4.0 -force_key_frames 'expr:gte(t,n_forced*4.0)' -crf 16  /tmpdir/crf_16.mpd

template-file: bigbuckbunny480p24x30s_fix_vbr_job003.txt

First Pass:

ffmpeg -i /videos/bigbuckbunny480p24x30s.y4m -nostats -threads 1 -map 0:0 -vcodec libx264 -x264-params keyint=96:min-keyint=96 -use_timeline 0 -use_template 0 -hls_playlist 1 -seg_duration 4.0 -force_key_frames 'expr:gte(t,n_forced*4.0)' -pass 1 -b:v 123456.0 -f null -

Second Pass:

ffmpeg -i /videos/bigbuckbunny480p24x30s.y4m -nostats -threads 1 -map 0:0 -vcodec libx264 -x264-params keyint=96:min-keyint=96 -use_timeline 0 -use_template 0 -hls_playlist 1 -seg_duration 4.0 -force_key_frames 'expr:gte(t,n_forced*4.0)' -pass 2 -b:v 123456.0 -f dash /tmpdir/crf_16.mpd