len0rd/rockbox
1
0
Fork 1
mirror of https://github.com/Rockbox/rockbox.git synced 2026-10-10 08:03:04 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions
rockbox/lib/rbcodec/codecs
History
Michael Giacomelli 11b12894ad wma: fix the level of noise coded high bands 
Low bitrate WMA files code their upper bands as noise at a given
power. Those bands came out 12 to 25 dB too quiet, which dulled
the treble. Two things were wrong.

The exponent pointer was moved too far in blocks whose exponents
have another resolution. This is ffmpeg's r20756 (f78501b264,
"Fix apparent 10l typos introduced in r8627"); r8627 was merged
here in 2f1da8d24a but the fix for it never was.

The fixed point gain of a band lost nearly all its precision: it
was zero for three bands in four in the file traced, and the sum
for a band's power overflowed in a quarter of them. Compute the
gain in 64 bits, once a band. The factor for the noise below the
first coded coefficient (WMA v1 only) was 16 bits too large and is
corrected by the same reasoning; no file here exercises it.

Checked with perfsim (Sansa e200v1 build) against ffmpeg's decode,
as the mean difference in band levels over the whole file:

  01 - Jane Austen (44.1 kHz, 32 kbps)   5.5 dB -> 0.0 dB
  07.Devil.In.My.Mind (same)             6.2 dB -> 0.0 dB
  beyonthepain907z (same)                6.8 dB -> 0.0 dB
  moshimoashitaga (same)                 2.8 dB -> 0.0 dB

Four more noise coded files, already within 0.3 dB, now match too.
The output of the 15 files without noise coding is byte-identical.
Files that use LSP exponents still differ in their top bands; that
is a separate fault in the LSP curve.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-05 20:47:12 -04:00
..
cRSID Revert "[BugFix] Enums are only 2 bytes on some Devices" 2024-11-24 11:38:16 -05:00
demac libdemac: reciprocal table for the pivot division on ARMv5+ 2026-10-05 10:19:38 -04:00
lib chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
liba52 chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libalac chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libasap chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libasf chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libatrac chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libayumi chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libcook chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libfaad chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libffmpegFLAC flac: ARM assembly for the 64-bit LPC filter 2026-10-05 12:19:09 -04:00
libgme chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libm4a libm4a: handle sparse chunk maps and video-first MP4 2026-09-07 09:17:27 -04:00
libmad chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libmusepack chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libopus opus: filter the PLC excitation in place 2026-09-30 11:25:30 -04:00
libpcm chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
librm Add "rbfs" prefix to native filesystem functions 2026-09-17 16:22:31 -04:00
libspc chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libspeex libspeex: Silence a spurious warning under Clang 2026-07-15 16:22:18 -04:00
libtremor chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libtta chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libwavpack chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
libwma wma: fix the level of noise coded high bands 2026-10-05 20:47:12 -04:00
libwmapro wmapro: fix the level and accuracy of 16 bit streams 2026-10-05 20:13:48 -04:00
libwmavoice chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
a52.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
a52_rm.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
aac.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
aac_bsf.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
adx.c fix warnings on some systems / format specifier mismatch 2024-12-07 11:07:44 -05:00
aiff.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
aiff_enc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
alac.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
ape.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
asap.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
atrac3_oma.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
atrac3_rm.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
au.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
ay.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
codec_crt0.c 3ds: Port refactor. 2026-09-01 08:39:07 -04:00
codecs.h chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
codecs.make codecs: link libarm_support for its division routines 2026-10-05 07:46:37 -04:00
cook.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
flac.c flac: cope with frames larger than one buffer request 2026-10-03 18:17:56 -04:00
gbs.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
hes.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
kss.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
mod.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
mp3_enc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
mpa.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
mpc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
nsf.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
opus.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
raac.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
sgc.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
shorten.c codecs: Fix elapsed time calculation for large files 2018-10-29 19:50:34 +01:00
sid.c SID: Don't uselessly upconvert from 16bpp mono to 28bpp stereo 2025-09-02 20:19:22 -04:00
smaf.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
SOURCES warble: fix build on targets with HAVE_RECORDING 2026-08-25 08:01:09 -04:00
spc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
speex.c build: Silence a pile of set-but-not-used warnings in codecs 2026-05-17 16:39:06 -04:00
tta.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
vgm.c Remove explicit 'enum codec_command_action' in codec API 2017-12-07 14:41:59 -05:00
vorbis.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
vox.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
vtx.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wav.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wav64.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wav_enc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wavpack.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wavpack_enc.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wma.c wma: decode every codec packet in an ASF payload 2026-10-05 20:47:12 -04:00
wmapro.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00
wmavoice.c chore: Get rid of *all* vestigal CVS '$Id:$' tags 2026-06-01 16:01:18 -04:00