Version 2.8

RELEASENOTES.md

@@ -1,3 +1,30 @@
+Version 2.8 – Stable Version
+----
+Version 2.8 is derived from version 2.7.10 with slight documentation updates. Here is a summary of changes between the last stable version – 2.6 – and this version. For full details, refer to the release notes here, back as far as 2.7.
+
+**New Feature**
+* For hardware mixers with a restricted range (including many cheaper USB DACS), the general `volume_range_db` can be used to specify a wider range than the hardware provides – the extra range is provided by in software.
+
+**Enhancements**
+* The `man` manual and the html version of it are automagically rebuilt if `xml2man` and friends are available.
+* Volume-setting metadata is now sent even when the volume level is to be ignored by Shairport Sync itself. 
+* Shairport Sync waits a little longer before asking for missing packets to be resent. Sometimes packets are just arriving slightly out of order and don't need to be asked for again.
+* The build scripts have been modified to be a little more compatible with standard practice.
+* A Continuous Integration (CI) system – Travis CI – is now used to do some limited build checking (thanks guys!).
+* Support added for compiling on Cygwin.
+* Added `rtptime` tags to metadata and picture metadata.
+* Replaced and improved the dither algorithm used with the software volume control. The new dither code gives a two bit peak-to-peak dither based on a Triangular Probability Distribution Function (TPDF).
+* Disabled picture sending if pictures haven’t been asked for.
+
+**Bug fixes**
+* Fixed a bug that prevented Shairport Sync from correctly setting the hardware mixer volume if it had been altered externally.
+* Modified the shutdown behaviour so that a shutdown followed immediately by a play request is handled properly. This was causing iOS 9.2 sometimes to drop the Airplay link between tunes.
+* Fixed a data-alignment bug that would cause a crash in certain circumstances on ARM processors with metadata enabled.
+* Corrected the names for a few settings tags.
+* Fixed some typos and misspellings.
+* Miscellaneous small bug fixes.
+
+
 Version 2.7.10 -- Development Version
 ----
 **New Feature**
@@ -60,7 +87,7 @@ http:https://www.freedesktop.org/software/systemd/man/daemon.html#Installing%20Systemd
 Version 2.7.3 -- Development Version
 ----
 **Bug Fix**
-* The dither code was broken in Shairport Sync and also less than ideal anyway. Fixed and improved. Dither is added whenever you use the software volume control at less than full volume. See http:https://www.ece.rochester.edu/courses/ECE472/resources/Papers/Lipshitz_1992.pdf for a very influential paper by Lipshitz, Wannamaker and Vanderkooy, 1992. The dither code in Shairport Sync was inherited from Shairport and does not conform to the recommendations in the paper -- specifically the implementation would give one bit of dither where the paper recommends two bits peak-to-peak. The other thing is that the inherited dither code was actually broken in Shairport Sync. So, the new dither code gives a two bit peak-to-peak dither based on a Triangular Propability Distributing Function (TPDF). It sounds like a very low-level white noise, unmodulated by the audio material. It would be nice if it was even lower, but it's better than listening to the artifacts present when dithering is disabled.
+* The dither code was broken in Shairport Sync and also less than ideal anyway. Fixed and improved. Dither is added whenever you use the software volume control at less than full volume. See http:https://www.ece.rochester.edu/courses/ECE472/resources/Papers/Lipshitz_1992.pdf for a very influential paper by Lipshitz, Wannamaker and Vanderkooy, 1992. The dither code in Shairport Sync was inherited from Shairport and does not conform to the recommendations in the paper -- specifically the implementation would give one bit of dither where the paper recommends two bits peak-to-peak. The other thing is that the inherited dither code was actually broken in Shairport Sync. So, the new dither code gives a two bit peak-to-peak dither based on a Triangular Probability Distribution Function (TPDF). It sounds like a very low-level white noise, unmodulated by the audio material. It would be nice if it was even lower, but it's better than listening to the artifacts present when dithering is disabled.
 
 Version 2.7.2 -- Development Version
 ----
@@ -78,7 +105,7 @@ Version 2.7.1 -- Development Version
 Version 2.7 -- Development Version
 ----
 **New Features**
-* Extend the volume range for some DACs. Background: some of the cheaper DACS have a very small volume range (that is, the ratio of the highest to the lowest volume, expressed in decibels). In some really cheap DACs it's only around 30 dB. That means that the difference betweeen the lowest and highest volume settings isn't large enough. With the new feature, if you set the `general` `volume_range_db` to more than the hardware mixer's range, Shairport Sync will combine the hardware mixer's range with a software attenuator to give the desired range. For example, suppose you want a volume range of 70 dB and the hardware mixer offers only 30 dB, then Shairport Sync will make up the other 40 dB with a software attenuator. One drawback is that, when the volume is being changed, there may be a slight delay (0.15 seconds by default) as the audio, whose volume may have been adjusted in software, propagates through the system. Another slight possible drawback is a slightly heavier load on the processor.
+* Extend the volume range for some DACs. Background: some of the cheaper DACS have a very small volume range (that is, the ratio of the highest to the lowest volume, expressed in decibels, is very small). In some really cheap DACs it's only around 30 dB. That means that the difference betweeen the lowest and highest volume settings isn't large enough. With the new feature, if you set the `general` `volume_range_db` to more than the hardware mixer's range, Shairport Sync will combine the hardware mixer's range with a software attenuator to give the desired range. For example, suppose you want a volume range of 70 dB and the hardware mixer offers only 30 dB, then Shairport Sync will make up the other 40 dB with a software attenuator. One drawback is that, when the volume is being changed, there may be a slight delay (0.15 seconds by default) as the audio, whose volume may have been adjusted in software, propagates through the system. Another slight possible drawback is a slightly heavier load on the processor.
 * Check for underflow a little better when buffer aliasing occurs on very bad connections...
 * Add extra debug messages to the alsa back end to diagnose strange DACs.
 * Add configuration file for the `libao` back end -- to change the buffer size and the latency offset, same as for stdout.