[FFmpeg-devel] [PATCH] RTP depacketizer for H.263

[Ronald S. Bultje]

Hi,

On Mon, Jan 25, 2010 at 10:05 AM, Martin Storsj? <martin at martin.st> wrote:
> On Mon, 25 Jan 2010, Ronald S. Bultje wrote:
>> > + ? ?int P, V, plen, pebit;
>> [..]
>> > + ? ?P = buf[0] & 0x04;
>> > + ? ?V = buf[0] & 0x02;
>>
>> Can you document what P and V are?
>
> Sure! Added a much more verbose comment in the updated patch, attached.

Some more:

> +    P = buf[0] & 0x04;
[..]
> +    if (av_new_packet(pkt, len + (P ? 2 : 0))) {

P>>1 (or assign P with buf[0]&0x4>>1).

> +     * pebit is the number of bits to ignore of the last byte of the extra
> +     * picture header.
[..]
> +    pebit = buf[1] & 0x03;

But it's unused. Better to document it nd just not actually assign the
bits at all. Also, some of the other bits are undocumented, is it
known what they are? Lastly, could you read buf[0]/buf[1] as a BE16
and easify the calculation of plen?

Ronald