问题
I get the general idea that the frame.data[] is interpreted depending on which pixel format is the video (RGB or YUV). But is there any general way to get all the pixel data from the frame? I just want to compute the hash of the frame data, without interpret it to display the image.
According to AVFrame.h:
uint8_t* AVFrame::data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
int AVFrame::linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Does this mean that if I just extract from data[i] for linesize[i] bytes then I get the full pixel information about the frame?
回答1:
linesize[i] contains stride for the i-th plane.
To obtain the whole buffer, use the function from avcodec.h
/**
* Copy pixel data from an AVPicture into a buffer, always assume a
* linesize alignment of 1. */
int avpicture_layout(const AVPicture* src, enum AVPixelFormat pix_fmt,
int width, int height,
unsigned char *dest, int dest_size);
Use
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
to calculate the required buffer size.
来源：https://stackoverflow.com/questions/19377938/how-to-get-raw-frame-data-from-avframe-data-and-avframe-linesize-without-spe