Load QP - 2023.1 English

H.264/H.265 Video Codec Unit v1.2 Solutions LogiCORE IP Product Guide (PG252)

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2023.1 English

Updating or loading QPs using LoadQP option is not supported at Gstreamer, but it is possible to use loadQP in livestreaming at Control software level. The QP table is passed an input along with input frame buffer using AL_Encoder_Process API. You must update pQPTable values for each frame in live-streaming.

bool AL_Encoder_Process(AL_HEncoder hEnc, AL_TBuffer * pFrame, AL_TBuffer * pQpTable)

Pushes a frame buffer to the encoder. According to the GOP pattern, this frame buffer could or could not be encoded immediately.


[in] hEnc Handle to an encoder object
[in] pFrame Pointer to the frame buffer to encode The pFrame buffer needs to have an associated AL_TSrcMetaData describing how the yuv is stored in memory. The memory of the buffer should not be altered while the encoder is using it. There are some restrictions associated to the source metadata. The chroma pitch has to be equal to the luma pitch and must be 32bits aligned and should be superior to the minimum supported pitch for the resolution (See AL_EncGetMinPitch()). The chroma offset shouldn't fall inside the luma block. The FourCC should be the same as the one from the channel (See AL_EncGetSrcFourCC()).
[in] pQpTable Pointer to an optional qp table used if the external qp table mode is enabled


If the function succeeds the return value is nonzero (true) If the function fails the return value is zero (false).