The new syntax is more extensible and more user-friendly.
This breaks the previous syntax, should not be an issue as possibly
no-one is already using anullsrc.
Behaviour has been changed to fail negotiation if fields have been
left empty.
Patch was originally based on a patch by Hemanth.
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
Add aconvert filter to perform sample format, channel layout, and
packing format conversion.
The aconvert code depends on audio conversion code in libavcodec, so
this requires a dependency on libavcodec.
Based on previous work by S.N. Hemanth Meenakshisundaram and Mina Nagy
Zaki, performed for the GSoC 2010 and 2011.
This list is mainly useful to be directly used as a parameter by the
audio sink buffer, when there is no need to force a specific channel
layout.
The list of formats is generated programmatically, and avoids channel
layouts not supported by libavfilter (with more than 8 channels).
We preferred to avoid compile-time generation in order to avoid some
unnecessary complexity (build hacks, generating code maintainance
etc.).
A more compact way to express this list through the use of macros
should be possible when libavfilter will support more than 8 channels,
as there will be no need to filter out channel layouts with more than
8 channels.
See thread:
Subject: [FFmpeg-devel] [PATCH] lavfi: add ff_all_channel_layouts internal symbol
Date: Sat, 20 Aug 2011 15:33:16 +0200
A function name should tell what the function does rather than what
the function returns. This also avoids possible conflicts
(e.g. between a function and a public list of all supported formats),
and clarifies the code.
Breaks audio API/ABI, add a backward compatibility layer for video
API/ABI.
These changes were forgotten in commits:
lavfi: simplify signature for avfilter_get_audio_buffer() and friends
(commit 2c0317419b)
and
lavfi: consistently use int for sample_rate in AVFilterLink and AVFilterBufferRefAudioProps
(commit 4381bddc9f)
The additional parameters were never used and are complicating the
function interface. Also, they were inconsistent with the way the
video API works.
So this assumes that a requested samples buffer will have *always* the
format specified in the requested link.
This breaks audio filtering API and ABI.
It's a hack which was created to allow for multiple options with
different defaults to refer to same field (e.g. 'b' vs 'ab'). There is
no need for it anymore.
This is done in order to clarify the non-video-specific nature of the
buffersink code, as the result of the video/audio API unification of
the previous commit, and for improving overall consistency.
The new API is more generic (no distinction between audio/video for
pulling frames), and avoids code duplication.
A backward compatibility layer is kept for avoiding tools ABI breaks
(only for the video binary interface, audio interface was never used
in the tools).
Fix GCC warning:
asrc_abuffer.c: In function ‘init’:
asrc_abuffer.c:258: warning: passing argument 1 of ‘strtok_r’ discards qualifiers from pointer target type
Stefano Sabatini
Stefano Sabatini
Mina Nagy Zaki
Michael Niedermayer
Bobby Bingham
Anton Khirnov
Diego Biurrun