[FFmpeg-devel] [PATCH]ffplay 2/2: Fix subtitle rendering for special cases

[Robert Swain]

2009/2/6 Bj?rn Axelsson <gecko at acc.umu.se>:
> On Thu, 5 Feb 2009, Michael Niedermayer wrote:
>> > blend_subrect_2.diff:
>> > Fix blend_subrect for even-width subrects positioned on odd columns.
>> >
>> > When a subrect starts on an odd column, the first column is rendered
>> > separately and the chroma pointers are increased by one as if two columns
>> > were rendered. If the subrect had an even width to start width, the rest
>> > of the subrect has now an odd width and the final column is rendered
>> > separately, also increasing the chroma pointers as if two columns were
>> > rendered. This results in the chroma part of the subtitle getting offset
>> > one additional sample to the right for each row.
>> > The effect can be seen in the first, the sixth and the seventh subtitles
>> > of the sample[1].
>>
>> this change looks wrong
>
> Here's a cleaner approach...

I'm not sure if I'm doing something wrong but I don't see any
subtitles when playing that sample using ffplay. What is required to
test this patch?

Regards,
Rob