[FFmpeg-devel] [PATCH] dts parser fails to parse DTS-HD Master streams due to changing frame size

elupus elupus
Wed Jun 11 17:38:15 CEST 2008

On Wed, 11 Jun 2008 11:19:22 +0300, Kostya wrote:

> On Wed, Jun 11, 2008 at 09:23:03AM +0200, Benjamin Larsson wrote:
>> [12 quoted lines suppressed]
> The reason is called DCA specification where it is stated that all frame
> sizes should be equal.

What I see wrong in the parser is that you consider framesize to be from
one startcode to the next startcode, not the encoded framesize as given by
the dts header. 

This means that like in the case of DTS HD, where there is extra "junk"
after the full core dts frame (which btw, will have same framesize as
previous frame), the parser will never find a valid end code.

Another error is that if this even happens once in the stream due to bit
errors, the parser will then never resync, as pc1->size is unconditionally
increased, and compared to the fixed pc1->framesize.

Also what happens with a TS stream transmitted over tv network, when they
for example change bitrate or channel count? wouldn't that change


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