shorten decoder is not lossless

[ami_stuff]

it looks like the last frame of the audio is not decoded compared to the official decoder

I did this:

ffmpeg -i test.shn ffmpeg.wav

shorten -x test.shn shorten.wav
ffmpeg -i shorten.wav shorten_ff.wav

and then compared "ffmpeg.wav" vs "shorten_ff.wav"

in hex editor ("shorter_ff.wav" file is a bit longer)

​http://www.datafilehost.com/d/e5b57ea1

C:\>ffmpeg -i test.shn out.wav
ffmpeg version N-73510-g033dc39 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-l
ibilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enab
le-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --en
able-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --ena
ble-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc
 --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enabl
e-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --ena
ble-decklink --enable-zlib
  libavutil      54. 28.100 / 54. 28.100
  libavcodec     56. 47.100 / 56. 47.100
  libavformat    56. 40.100 / 56. 40.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 21.100 /  5. 21.100
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.100 /  1.  2.100
  libpostproc    53.  3.100 / 53.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, shn, from 'test.shn':
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Audio: shorten, 44100 Hz, 2 channels, s16p
Output #0, wav, to 'out.wav':
  Metadata:
    ISFT            : Lavf56.40.100
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, stereo, s16
, 1411 kb/s
    Metadata:
      encoder         : Lavc56.47.100 pcm_s16le
Stream mapping:
  Stream #0:0 -> #0:0 (shorten (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
Multiple frames in a packet from stream 0
size=    5170kB time=00:00:30.00 bitrate=1411.5kbits/s
video:0kB audio:5170kB subtitle:0kB other streams:0kB global headers:0kB muxing
overhead: 0.001473%

[Cigaes]

FFmpeg includes some metadata in WAVE files that other software rarely use, your comparison may be detecting just that. You need to extract to raw PCM to be sure.

[ami_stuff]

Replying to Cigaes:

FFmpeg includes some metadata in WAVE files that other software rarely use, your comparison may be detecting just that. You need to extract to raw PCM to be sure.

Ok thanks for the info, but in this case output from ffmpeg and shorten still doesn't match:

ffmpeg -i test.shn -f s16le ffmpeg.pcm

shorten -x test.shn shorten.wav
ffmpeg -i shorten.wav -f s16le shorten_ff.pcm

[Carl Eugen Hoyos]

The FFmpeg output is 512 bytes shorter than the shorten output.

[ami_stuff]

also the output from:

​https://samples.mplayerhq.hu/A-codecs/lossless/luckynight.mlp
​https://samples.mplayerhq.hu/A-codecs/lossless/luckynight.rmvb

doesn't match (some differences at the end of the file):

​https://samples.mplayerhq.hu/A-codecs/lossless/luckynight.wav.bz2

[ami_stuff]

Replying to cehoyos:

The FFmpeg output is 512 bytes shorter than the shorten output.

looks like regression

ffmpeg -i test.shn -f s16le ffmpeg.pcm

ffmpeg 0.8 - 5294592
ffmpeg 1.0.1 - 5294080

[Carl Eugen Hoyos]

For the given sample this is a regression since b4b58485135dbc37a6cf8a57196157b1d67d13e1 related to ticket #1250

[Elon Musk]

Fixed in 966d43d7786d1a95162e3feff1d5bfbcb58e571f.