[FFmpeg-devel] [PATCH v3 1/4] avcodec/libjxldec: use internal AVFrame as buffered space

Leo Izen leo.izen at gmail.com
Sat Jun 24 18:24:49 EEST 2023


On 6/24/23 07:49, James Almer wrote:
> 
> On 6/24/2023 1:38 AM, Leo Izen wrote:
>> Before this commit, the decoder erroneously assumes that the AVFrame
>> passed to the receive_frame is the same one each time. Now it keeps an
>> internal AVFrame to write into, and copies it over when it's done.
>> ---
>>   libavcodec/libjxldec.c | 40 +++++++++++++++++++++++-----------------
>>   1 file changed, 23 insertions(+), 17 deletions(-)
>>
>> diff --git a/libavcodec/libjxldec.c b/libavcodec/libjxldec.c
>> index 50417bcb02..cea7ea0d3b 100644
>> --- a/libavcodec/libjxldec.c
>> +++ b/libavcodec/libjxldec.c
>> @@ -58,6 +58,7 @@ typedef struct LibJxlDecodeContext {
>>       int64_t frame_duration;
>>       int prev_is_last;
>>       AVRational timebase;
>> +    AVFrame *frame;
>>   } LibJxlDecodeContext;
>>   static int libjxl_init_jxl_decoder(AVCodecContext *avctx)
>> @@ -104,6 +105,9 @@ static av_cold int 
>> libjxl_decode_init(AVCodecContext *avctx)
>>       ctx->avpkt = avctx->internal->in_pkt;
>>       ctx->pts = 0;
>> +    ctx->frame = av_frame_alloc();
>> +    if (!ctx->frame)
>> +        return AVERROR(ENOMEM);
>>       return libjxl_init_jxl_decoder(avctx);
>>   }
>> @@ -351,10 +355,12 @@ static int libjxl_receive_frame(AVCodecContext 
>> *avctx, AVFrame *frame)
>>           size_t remaining;
>>           if (!pkt->size) {
>> +            av_log(avctx, AV_LOG_DEBUG, "Fetching new packet\n");
>>               av_packet_unref(pkt);
>>               ret = ff_decode_get_packet(avctx, pkt);
>>               if (ret < 0 && ret != AVERROR_EOF)
>>                   return ret;
>> +            av_log(avctx, AV_LOG_DEBUG, "Fetched packet of size: 
>> %d\n", pkt->size);
>>               if (!pkt->size) {
>>                   /* jret set by the last iteration of the loop */
>>                   if (jret == JXL_DEC_NEED_MORE_INPUT) {
>> @@ -389,10 +395,6 @@ static int libjxl_receive_frame(AVCodecContext 
>> *avctx, AVFrame *frame)
>>               return AVERROR_INVALIDDATA;
>>           case JXL_DEC_NEED_MORE_INPUT:
>>               av_log(avctx, AV_LOG_DEBUG, "NEED_MORE_INPUT event 
>> emitted\n");
>> -            if (!pkt->size) {
>> -                av_packet_unref(pkt);
>> -                return AVERROR(EAGAIN);
>> -            }
>>               continue;
>>           case JXL_DEC_BASIC_INFO:
>>               av_log(avctx, AV_LOG_DEBUG, "BASIC_INFO event emitted\n");
>> @@ -421,16 +423,18 @@ static int libjxl_receive_frame(AVCodecContext 
>> *avctx, AVFrame *frame)
>>               continue;
>>           case JXL_DEC_COLOR_ENCODING:
>>               av_log(avctx, AV_LOG_DEBUG, "COLOR_ENCODING event 
>> emitted\n");
>> -            if ((ret = libjxl_color_encoding_event(avctx, frame)) < 0)
>> +            if ((ret = libjxl_color_encoding_event(avctx, 
>> ctx->frame)) < 0)
>>                   return ret;
>>               continue;
>>           case JXL_DEC_NEED_IMAGE_OUT_BUFFER:
>>               av_log(avctx, AV_LOG_DEBUG, "NEED_IMAGE_OUT_BUFFER event 
>> emitted\n");
>> -            if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
>> +            ret = ff_get_buffer(avctx, ctx->frame, 0);
>> +            if (ret < 0)
>>                   return ret;
>> -            ctx->jxl_pixfmt.align = frame->linesize[0];
>> -            if (JxlDecoderSetImageOutBuffer(ctx->decoder, 
>> &ctx->jxl_pixfmt, frame->data[0], frame->buf[0]->size)
>> -                != JXL_DEC_SUCCESS) {
>> +            ctx->jxl_pixfmt.align = ctx->frame->linesize[0];
>> +            if (JxlDecoderSetImageOutBuffer(ctx->decoder, 
>> &ctx->jxl_pixfmt,
>> +                    ctx->frame->data[0], ctx->frame->buf[0]->size)
>> +                    != JXL_DEC_SUCCESS) {
>>                   av_log(avctx, AV_LOG_ERROR, "Bad libjxl dec need 
>> image out buffer event\n");
>>                   return AVERROR_EXTERNAL;
>>               }
>> @@ -444,8 +448,8 @@ static int libjxl_receive_frame(AVCodecContext 
>> *avctx, AVFrame *frame)
>>           case JXL_DEC_FRAME:
>>               av_log(avctx, AV_LOG_DEBUG, "FRAME event emitted\n");
>>               if (!ctx->basic_info.have_animation || ctx->prev_is_last) {
>> -                frame->pict_type = AV_PICTURE_TYPE_I;
>> -                frame->flags |= AV_FRAME_FLAG_KEY;
>> +                ctx->frame->pict_type = AV_PICTURE_TYPE_I;
>> +                ctx->frame->flags |= AV_FRAME_FLAG_KEY;
>>               }
>>               if (ctx->basic_info.have_animation) {
>>                   JxlFrameHeader header;
>> @@ -464,20 +468,21 @@ static int libjxl_receive_frame(AVCodecContext 
>> *avctx, AVFrame *frame)
>>               /* full image is one frame, even if animated */
>>               av_log(avctx, AV_LOG_DEBUG, "FULL_IMAGE event emitted\n");
>>               if (ctx->iccp) {
>> -                AVFrameSideData *sd = 
>> av_frame_new_side_data_from_buf(frame, AV_FRAME_DATA_ICC_PROFILE, 
>> ctx->iccp);
>> +                AVFrameSideData *sd = 
>> av_frame_new_side_data_from_buf(ctx->frame, AV_FRAME_DATA_ICC_PROFILE, 
>> ctx->iccp);
>>                   if (!sd)
>>                       return AVERROR(ENOMEM);
>>                   /* ownership is transfered, and it is not ref-ed */
>>                   ctx->iccp = NULL;
>>               }
>>               if (avctx->pkt_timebase.num) {
>> -                frame->pts = av_rescale_q(ctx->pts, ctx->timebase, 
>> avctx->pkt_timebase);
>> -                frame->duration = av_rescale_q(ctx->frame_duration, 
>> ctx->timebase, avctx->pkt_timebase);
>> +                ctx->frame->pts = av_rescale_q(ctx->pts, 
>> ctx->timebase, avctx->pkt_timebase);
>> +                ctx->frame->duration = 
>> av_rescale_q(ctx->frame_duration, ctx->timebase, avctx->pkt_timebase);
>>               } else {
>> -                frame->pts = ctx->pts;
>> -                frame->duration = ctx->frame_duration;
>> +                ctx->frame->pts = ctx->pts;
>> +                ctx->frame->duration = ctx->frame_duration;
>>               }
>>               ctx->pts += ctx->frame_duration;
>> +            av_frame_move_ref(frame, ctx->frame);
>>               return 0;
>>           case JXL_DEC_SUCCESS:
>>               av_log(avctx, AV_LOG_DEBUG, "SUCCESS event emitted\n");
>> @@ -508,6 +513,7 @@ static av_cold int 
>> libjxl_decode_close(AVCodecContext *avctx)
>>           JxlDecoderDestroy(ctx->decoder);
>>       ctx->decoder = NULL;
>>       av_buffer_unref(&ctx->iccp);
>> +    av_frame_free(&ctx->frame);
>>       return 0;
>>   }
>> @@ -521,7 +527,7 @@ const FFCodec ff_libjxl_decoder = {
>>       .init             = libjxl_decode_init,
>>       FF_CODEC_RECEIVE_FRAME_CB(libjxl_receive_frame),
>>       .close            = libjxl_decode_close,
>> -    .p.capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_OTHER_THREADS,
> 
> Why remove DR1? ff_get_buffer() is still called and user provided 
> buffers should still work fine.
> 

I had tested it earlier and it failed an assert. However, it appears 
that it's working fine now with it, so I'll add it back in.

- Leo Izen


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