Port MPlayer tinterlace filter from MPlayer, with some ideas taken
from the FFmbc/libavfilter port, with the following main differences:
* added support for full-scale YUVJ formats
* added support for YUVA420P
* request_frame() on the filter is forced to return a frame
* some code factorization (related to the copy_picture_fields() function)
* fixed black padding values for mode 3
Rationale: avfilter_copy_frame_props() was already defined in
libavfilter/avcodec.h, and keeping the lavc/lavfi API glue localized in a
specific file should ease maintainance and help the ones which use
libavfilter without depending on libavcodec.
It makes more sense for a bit mask to use an unsigned type.
The change should be source and binary compatible on all
supported systems, hence micro version bump.
Fixes a few invalid shifts.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Factorize code, extend the functionality of the filter, and make it
return empty buffers. This is useful for filters which ignore the input
frames content.
This is also changing the syntax of the nullsrc source, and dropping the
framerate expression evaluation, which does not look particularly useful.
The licence was changed from GPL to LGPL with explicit approval from
the original author.
See thread:
Subject: [FFmpeg-devel] [PATCH] lavfi: add rgbtestsrc source,
ported from MPlayer libmpcodecs
Date: Mon, 11 Jul 2011 16:32:41 +0200
Signed-off-by: Anton Khirnov <anton@khirnov.net>
With the following additions:
* support to gray format
* support to yuva420p format
* parametric luma/chroma/alpha radius
* consistency check on the radius values, avoid crashes with invalid values
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Or in other word, do not go to the next line when the text cannot be
rendered within the frame.
The rationale is that wrapping is hard to manage, as it depends on the
position of the text, thus making hard/impossible to compute the size
occupied by the rendered text, and makes the filter behavior
unpredictible with moving text (implemented in a pending patch).
Also the current wrapping code is very limited (for example it splits
words in the middle), and correctly handling wrapping requires much
more complexity (alignment, gravity, word parsing etc.), while
drawtext is meant to be only a thin wrapper around libfreetype, so
such advanced features don't belong here.
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.
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.
Stefano Sabatini
Nicolas George
Stefano Sabatini
Anton Khirnov
Michael Niedermayer
Diego Biurrun
Clément Bœsch
Mans Rullgard
Clément Bœsch
Mark Himsley
Mina Nagy Zaki