[FFmpeg-devel] [PATCH 2/4] avcodec/qtrle: return last frame even if unchanged

[Marton Balint]

On Mon, 12 Aug 2019, Michael Niedermayer wrote:

> On Fri, May 31, 2019 at 10:28:15PM +0200, Marton Balint wrote:
>>
>>
>> On Thu, 30 May 2019, Michael Niedermayer wrote:
>>
>>> Fixes: Ticket7880
>>>
>>> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
>>> ---
>>> libavcodec/qtrle.c        | 42 +++++++++++++++++++++++++++++++++++----
>>> tests/ref/fate/qtrle-8bit |  1 +
>>> 2 files changed, 39 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/libavcodec/qtrle.c b/libavcodec/qtrle.c
>>> index 2c29547e5a..4add1aded6 100644
>>> --- a/libavcodec/qtrle.c
>>> +++ b/libavcodec/qtrle.c
>>> @@ -45,6 +45,8 @@ typedef struct QtrleContext {
>>>
>>>    GetByteContext g;
>>>    uint32_t pal[256];
>>> +    int need_flush;
>>> +    AVPacket flush_pkt;
>>> } QtrleContext;
>>>
>>> #define CHECK_PIXEL_PTR(n)                                                            \
>>> @@ -444,6 +446,12 @@ static av_cold int qtrle_decode_init(AVCodecContext *avctx)
>>>    return 0;
>>> }
>>>
>>> +static void qtrle_flush(AVCodecContext *avctx){
>>> +    QtrleContext *s = avctx->priv_data;
>>> +
>>> +    s->need_flush = 0;
>>> +}
>>> +
>>> static int qtrle_decode_frame(AVCodecContext *avctx,
>>>                              void *data, int *got_frame,
>>>                              AVPacket *avpkt)
>>> @@ -454,11 +462,32 @@ static int qtrle_decode_frame(AVCodecContext *avctx,
>>>    int has_palette = 0;
>>>    int ret, size;
>>>
>>> +    if (!avpkt->data) {
>>> +        if (s->need_flush) {
>>> +            s->need_flush = 0;
>>> +            if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
>>> +                return ret;
>>> +            s->frame->pkt_pos      = s->flush_pkt.pos;
>>> +            s->frame->pkt_duration = s->flush_pkt.duration;
>>> +            s->frame->pkt_dts      = s->flush_pkt.dts;
>>> +            s->frame->pkt_pts      =
>>> +            s->frame->pts          = s->flush_pkt.pts;
>>
>> This does not seem to work, because the magic in decode_simple_internal in
>> decode.c will overwrite these fields. Alternative approach which seems to
>> work is assigning the AVPacket fields instead:
>>
>>             avpkt->pos      = s->flush_pkt.pos;
>>             avpkt->duration = s->flush_pkt.duration;
>>             avpkt->dts      = s->flush_pkt.dts;
>>             avpkt->pts      = s->flush_pkt.pts;
>>
>> Looks a bit ugly, but as far as I see we are using an internal packet, and
>> not the one provided by the user, so it might be OK.
>
> ill repost this with a different, less ugly variant.
>
> Please recheck if that works!

Seems fine now, thanks.

Regards,
Marton