There have been multiple bugs caused by inconsistencies here.

Based on an idea from Michael Niedermayer.

CC: libav-stable@libav.org

This makes sure the reset flag gets set when SBR gets turned back on
and sets control variables for unguided mode back to their defaults.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

If the next header frame codes zero envelopes the previous frame's
values will be used. Consequently the invalid values must be cleared.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Prevents a signflip in the counter, and a subsequent crash because of
overreads/overwrites.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Correct handling of errors to prevent hags or crashes is very complex
otherwise.

The frame initializing is also moved from decode_slice() to
decode_frame() for clarity.

Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Diego Biurrun <diego@biurrun.de>

This matches the output size required for audio_resample()

Allows for removing a goto and makes the code easier to follow.

This prevents a SIGFPE later on.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: Libav-stable@libav.org

Prevents crash (double free) when free()ing the original packet.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Prevents infinite loop because min_channel_len never increments.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Prevents overreads beyond buffer boundaries.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Prevents overwrites when some subframes only encode some channels.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>

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

Fixes encoding very large pictures.

Thanks to Костя for providing the formula.

CC: libav-stable@libav.org

Also set CODEC_CAP_DELAY to indicate that decoder may still have some
undecoded data left in internal buffer.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>

Break some of the longer sections into smaller sensible pieces;
make some option descriptions and option ordering more consistent.

The first frame pts must be saved until we have 8 frames since RoQ audio
requires 8 frames in the first packet.