Fixes valgrind uninitialized memory errors when decoding png.

CC:libav-stable@libav.org

CC:libav-stable@libav.org

Fixes build without threads after
759001c534.

Signed-off-by: Martin Storsjö <martin@martin.st>

CC:libav-stable@libav.org

Returning 0 may result in an infinite loop in valid calling programs. A
decoder should never return 0 without producing any output.

CC:libav-stable@libav.org

Avoids an infinite loop in the calling programs with decoder not
consuming any input and not returning output.

CC:libav-stable@libav.org

Avoids an infinite loop in the calling programs with decoder not
consuming any input and not returning output.

CC:libav-stable@libav.org

CC:libav-stable@libav.org

When there is just 1 byte remanining in the buffer, nothing will be read
and the loop will continue forever. Check that there are at least 8
bytes, which are always read at the beginning.

CC:libav-stable@libav.org

The loop a few lines below the xan_unpack() call accesses up to
dec_size * 2 bytes into y_buffer, so dec_size must be limited to
buffer_size / 2.

CC:libav-stable@libav.org

It got broken in 0f13cd3187.

CC:libav-stable@libav.org

CC:libav-stable@libav.org

Its replacement is still not ready.

It is not used inside lavc anywhere and now it makes no sense to export
it.

It has been broken for over a year without anyone complaining or
noticing, thus proving that nobody ever uses it.

This should ensure that a valid channel layout is always set on a frame,
until a better solution is implemented.

This is the most that can be represented with the current channel layout
system. This limit should be raised/removed when a better system is
implemented.

This misfeature is most likely completely useless and conflicts with
removing the mpegvideo-specific fields from AVFrame. In the improbable
case it is actually useful, it should be reimplemented in a better way.

Add AVBuffer-based reference counting API to it.

This field is private and should not be present in a public struct. It
is only used in DXVA with mpegvideo-based decoders currently.

This will allow us to avoid copying the packets in many cases.

This breaks ABI.

When parsing the Xing/Info tag, don't set the bit rate if it's an Info tag.

When parsing the stream, don't override the bit rate if it's already set,
otherwise calculate the mean bit rate from parsed frames. This way, the bit
rate will be set correctly both for CBR and VBR streams.

CC:libav-stable@libav.org

Signed-off-by: Anton Khirnov <anton@khirnov.net>

This breaks the dependency of mpegvideo on error_resilience allowing
compilation of components that depend on the former w/o the latter.

Make sure the behavior does not change with the locale.

Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Martin Storsjö <martin@martin.st>

This makes the decoder independent of mpegvideo.

This copy of the draw_horiz_band code is simplified compared to
the "generic" mpegvideo one which still has a number of special
cases for different codecs.

Signed-off-by: Martin Storsjö <martin@martin.st>

Make av_get_codec_tag_string() show codec tag string characters in a more
intelligible ways. For example the ascii char "@" is used as a number, so
should be displayed like "[64]" rather than as a printable character.

Apart alphanumeric chars, only the characters ' ' and '.' are used
literally in codec tags, all the other characters represent numbers.

This also avoids relying on locale-dependent character class functions.

Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Martin Storsjö <martin@martin.st>

Not all hwaccels implement all codecs, so using one single list for
multiple such codecs means some codecs will be represented in the list,
even though they don't actually handle that codec. Copying specific
lists in each codec fixes that.

Signed-off-by: Martin Storsjö <martin@martin.st>