X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=ycbcr.h;h=e4ca43fa3259f04bd84f27d826dcf5db362a1b02;hp=4eb9e73185794fc0118ec2590e4303892dfa8595;hb=25162b5457057af3ebcc1649571eeeb923e90098;hpb=e8499e3e9892a74c7882af4be14ccdc1e3d92c2b diff --git a/ycbcr.h b/ycbcr.h index 4eb9e73..e4ca43f 100644 --- a/ycbcr.h +++ b/ycbcr.h @@ -29,9 +29,10 @@ // range, 10-bit goes out of range (white gets to 942), while if you select // 10-bit range, 8-bit gets only to 234, making true white impossible. // -// We currently support the 8-bit ranges only, since all of our Y'CbCr -// handling effects happen to support only 8-bit at the moment. We will need -// to fix this eventually, though, with an added field to YCbCrFormat. +// Thus, you will need to specify the actual precision of the Y'CbCr source +// (or destination); the num_levels field is the right place. Most people +// will want to simply set this to 256, as 8-bit Y'CbCr is the most common, +// but the right value will naturally depend on your input. #include "image_format.h" @@ -48,8 +49,8 @@ struct YCbCrFormat { // JPEG uses the Rec. 601 luma coefficients, but full range. bool full_range; - // Currently unused, but should be set to 256 for future expansion, - // indicating 8-bit interpretation (see file-level comment). + // Set to 2^n for n-bit Y'CbCr (e.g. 256 for 8-bit Y'CbCr). + // See file-level comment. int num_levels; // Sampling factors for chroma components. For no subsampling (4:4:4),