Git Inbox Mirror of the ffmpeg-devel mailing list - see https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
 help / color / mirror / Atom feed
From: Martijn van Beurden <mvanb1@gmail.com>
To: ffmpeg-devel@ffmpeg.org
Cc: Martijn van Beurden <mvanb1@gmail.com>
Subject: [FFmpeg-devel] [PATCH v4 0/2] 32bps FLAC patches
Date: Sat,  3 Sep 2022 11:21:42 +0200
Message-ID: <20220903092144.569716-1-mvanb1@gmail.com> (raw)

Recently libFLAC gained the ability (not in any released version yet
though) to create FLAC files containing 32-bit int PCM samples. To
keep complexity reasonable, the choice was made to limit residuals
to 32-bit integers, which the encoder must make sure of. In case
the encoder cannot find any predictor of which the residuals fit
this limit, it must default to using a verbatim subframe. Tests have
shown that this does not happen often (<0.1% of subframes on a
music corpus of various styles). See also discussion here:
https://github.com/ietf-wg-cellar/flac-specification/pull/148

These two patches implement decoding and encoding following this
format.

Changes since v1:
fix copy-paste error in encoder, several invocations of
lpc_encode_choose_datapath used wrong parameters, making FATE fail as
compression was less than it should be

Changes since v2:
Rebased decoder part as it didn't apply anymore

Changes since v3:
Moved put_golomb part to flacenc.c (as it is now quite specific to FLAC)
and renamed put_sbits64 to put_sbits63 (and changed assert accordingly)

Martijn van Beurden (2):
  libavcodec/flacdec: Implement decoding of 32 bit-per-sample PCM
  libavcodec/flacenc: Implement encoding of 32 bit-per-sample PCM

 libavcodec/flac.c       |   4 +-
 libavcodec/flacdec.c    | 248 +++++++++++++++++--
 libavcodec/flacenc.c    | 519 ++++++++++++++++++++++++++++++++--------
 libavcodec/get_bits.h   |  12 +
 libavcodec/mathops.h    |   9 +
 libavcodec/put_bits.h   |   7 +
 libavcodec/put_golomb.h |  14 --
 7 files changed, 674 insertions(+), 139 deletions(-)

-- 
2.30.2

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".

             reply	other threads:[~2022-09-03  9:22 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-03  9:21 Martijn van Beurden [this message]
2022-09-03  9:21 ` [FFmpeg-devel] [PATCH v4 1/2] libavcodec/flacdec: Implement decoding of 32 bit-per-sample PCM Martijn van Beurden
2022-09-14 13:03   ` Andreas Rheinhardt
2022-09-14 15:21     ` Martijn van Beurden
2022-09-14 15:48       ` Paul B Mahol
2022-09-14 17:10       ` Andreas Rheinhardt
2022-09-03  9:21 ` [FFmpeg-devel] [PATCH v4 2/2] libavcodec/flacenc: Implement encoding " Martijn van Beurden
2022-09-10 10:32 ` [FFmpeg-devel] [PATCH v4 0/2] 32bps FLAC patches Martijn van Beurden
2022-09-10 13:22   ` Paul B Mahol

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220903092144.569716-1-mvanb1@gmail.com \
    --to=mvanb1@gmail.com \
    --cc=ffmpeg-devel@ffmpeg.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Git Inbox Mirror of the ffmpeg-devel mailing list - see https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://master.gitmailbox.com/ffmpegdev/0 ffmpegdev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 ffmpegdev ffmpegdev/ https://master.gitmailbox.com/ffmpegdev \
		ffmpegdev@gitmailbox.com
	public-inbox-index ffmpegdev

Example config snippet for mirrors.


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git