On 17/12/2018 18:45, ggeng wrote: > Hi, > > I am using libav to decode a video (following the demo code available > online), and I am trying to pre-allocate memory that the decoded frame data > will be written to. Ultimately, I would like to have pFrame->data[0] to be > in a region of memory I pre-allocate. > > Following examples online, I am able to set pFrame->data as so: > > *// Determine required buffer size and allocate buffer* > int numBytes; > numBytes = av_image_get_buffer_size(pixFmt, width, height, 1); > (uint8_t*) dataBuff = (uint8_t*) malloc (numBytes * sizeof(uint8_t)); > > *// Assign buffer to image planes in pFrame* > av_image_fill_arrays(frame->data, frame->linesize, dataBuff, pixFmt, width, > height, 1); > > However, I found that this call: > > ret = avcodec_receive_frame(pCodecContext, pFrame) > > will always write the decoded frame data to be somewhere else, and allocate > its own memory for pFrame->data, completely ignoring the dataBuffer I set to > pFrame->data before. > > Is there a way to get around this? Either by decoding video without a call > to avcodec_receive_frame or a way to set the memory for the data?
Have a look at the AVCodecContext.get_buffer2 callback. - Mark _______________________________________________ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user To unsubscribe, visit link above, or email libav-user-requ...@ffmpeg.org with subject "unsubscribe".
