avformat/img2dec: make image2dec capable to be used from seperate demuxers

Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat: add image2 alias pix demuxer

Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat: add image2 brender pix demuxer

Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/img2dec: Use avformat probing interface to identify format if it has not been otherwise identified

This is used only for distinguishing .pix formats for now.
Which is the only case that has image2 demuxers currently

Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/img2dec: try to read PROBE_BUF_MIN instead of just enough for .pix probing

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/img2_alias_pix: rewrite probe function

Fixes probetest failure

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/xbmdec: redesign parser to handle more cases

The new code is more tolerant on the syntax

Fixes decoding of bm1.xbm

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/vp7: check buffer size

Fixes overread
Fixes Ticket 3501
Found-by: Piotr Bandurski <ami_stuff@o2.pl>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Support raw dvdsub palette as stored on normal dvd's

This is how the palette is stored on dvd's. Currently
only xbmc passes the palette information to libavcodec
this way.
Check return value of avio_seek and avoid modifying state if it fails

The code still modifies state if the timestamp is not found. Not
sure exactly how to avoid that.
asf hacks
if av_read_packet returns AVERROR_IO, we are done. ffmpeg's codecs might or might not handle returning any completed demuxed packets correctly
added: Ticket #7187, TV Teletext support for DVB EBU Teletext streams
Don't accept mpegts PMT that isn't current
Don't reparse PMT unless it's version has changed
Read PID timestamps as well as PCR timestamps to find location in mpegts stream
Get stream durations using read_timestamp
changed: allow 4 second skew between streams in mov before attempting to seek
fixed: memleak in mpegts demuxer on some malformed (??) mpegts files with too large pes packets

at-visions sample file brokenStream.mpg
Speed up mpegts av_find_stream_info