On Mon, 10 Mar 2014 16:18:27 -0700 Ricky Huang <[email protected]> wrote:
> Hello all, > > I am writing code that extracts the luminance component of an input video > using my own custom filter in libavfilter - specifically I am extracting it > from "PIX_FMT_YUV420P" a video and I am wondering how to go about doing so. > According to the pixfmt.h header: > > > > PIX_FMT_YUV420P, ///< planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 > > Y samples) > > I am not sure how to interpret that. Assuming I am doing this in my > draw_slice() function. It has the definition of: > > > > static void draw_slice(AVFilterLink *inlink, int y0, int h, int slice_dir) > > I know I can get to the input data plane by: > > > > AVFilterBufferRef *cur_pic = link->cur_buf; > > uint8_t *data = cur_pic->data[0]; I think this functionality was removed long ago. You're supposed to write/read AVFrames from the filters. > But there are multiple "planes" in the data. Does data[0], data[1], data[2] > correspond to each of the Y, U, V channels? Yes, for YUV420P. > Also, once I am able to point my pointer at the correct coordinate, how > should I interpret the extracted result (float, int, etc)? > > > Thank you in advance. _______________________________________________ Libav-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/libav-user
