By default, each incoming buffer is copied into the decoder internal circular buffer, and the frame boundaries are (re-)detected afterwards by the decoder itself. This prevents it from keeping a true 1-to-1 relationship between the input buffer and decoded output frame. An application can try to retrieve the 1-to-1 relationship based on the decoding order, but this is not reliable in case of error concealment. The circular buffer in the decoder can be bypassed for use cases where the incoming buffers are frame or slice aligned. In this case, the decoder can directly work on the input buffer when using DMA input buffers. Any associated metadata can be retrieved on the output callback.
When --split-input is enabled, the decoder has a 1-to-1 mapping
for input and output buffers. When disabled, the decoder copies all input buffers to
internal circular buffer and processes them.
ctrlsw-decoder -hevc --split-input -in in.hevc -out out.yuvWhen split-input mode is enabled for decoder, input to decoder should be aligned with the frame (AU) or slice (NAL unit) boundary. Part of AU or NAL is not allowed.
gst-launch-1.0 filesrc location=in.mp4 ! qtdemux name=demux demux.video_0 ! h264parse ! video/x-h264, alignment=au ! omxh264dec low-latency=0 ! queue max-size-bytes=0 ! fakevideosink