[FFmpeg-devel] [PATCH 2/3] mpegvideo_parser: parse the output picture number

[Jan Ekström]

On Sun, Feb 11, 2018 at 7:52 PM, Michael Niedermayer
<michael at niedermayer.cc> wrote:
>
> should be ok unless its intended to also restore the MSB
>

The value seemed to be 10bit and if the pointer is at the position
right after the picture_start_code, then `buf[0] << 2` would move the
8 bits left of data two bits leftwards, and `buf[1] >> 6` would then
move the topmost bits of the following byte to be the bottom-most
bits.

Unless you mean that there's a forgotten `(uint16_t)` there as the end
value has 10 bits of effective data, making the correct way of doing
it something a la `(((uint16_t)buf[0]) << 2) | (((uint16_t)buf[1]) >>
6)`?

> Theres no code using output_picture_number currently
>

Seems like some API users utilize this value.


Jan