On Thu, 2017-04-13 at 09:40 -0700, Steve Longerbeam wrote: [...] > >> @@ -804,12 +804,29 @@ static void prp_try_fmt(struct prp_priv *priv, > >> &sdformat->format.height, > >> infmt->height / 4, MAX_H_SRC, > >> H_ALIGN_SRC, S_ALIGN); > >> + > >> + /* > >> + * The Image Converter produces fixed quantization > >> + * (full range for RGB, limited range for YUV), and > >> + * uses a fixed Y`CbCr encoding (V4L2_YCBCR_ENC_601). > >> + * For colorspace and transfer func, just propagate > >> + * from the sink. > >> + */ > >> + sdformat->format.quantization = > >> + ((*cc)->cs != IPUV3_COLORSPACE_YUV) ? > >> + V4L2_QUANTIZATION_FULL_RANGE : > >> + V4L2_QUANTIZATION_LIM_RANGE; > >> + sdformat->format.ycbcr_enc = V4L2_YCBCR_ENC_601; > > > > Support for V4L2_YCBCR_ENC_709 and quantization options could be added > > to the IPUv3 core code, so this limitation could be relaxed later. > > Yes, I was going to mention that too. We can add coefficient tables > to ipu-ic for all the encodings enumerated in enum v4l2_ycbcr_encoding. Exactly. > I know that quantization is programmable in the DP, but is it in the > IC? AFAICT there is none. We have a freely programmable 4x3 matrix multiplication both before and after processing in each task, and there is a saturation mode switch that can limit the first component to (16...235) and the other two to (16...240). That should be enough for at least full/limited range YCbCr quantizations. So we apparently can't saturate to limited range RGB, but for example full-range -> limited-range RGB conversions should be perfectly possible. regards Philipp _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
