diff options
| -rw-r--r-- | gst-libs/gst/video/video-converter.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/gst-libs/gst/video/video-converter.c b/gst-libs/gst/video/video-converter.c index 61c3ab574..9ee481f72 100644 --- a/gst-libs/gst/video/video-converter.c +++ b/gst-libs/gst/video/video-converter.c @@ -1980,13 +1980,33 @@ chain_convert_to_YUV (GstVideoConverter * convert, GstLineCache * prev, if (idx == 0 && !convert->pack_rgb) { color_matrix_set_identity (&convert->to_YUV_matrix); - compute_matrix_to_YUV (convert, &convert->to_YUV_matrix, FALSE); - /* matrix is in 0..255 range, scale to pack bits */ + /* When gamma remap is enabled, we do + * 1) converts to ARGB64 linear RGB + * - if input is 8bits, convert to ARGB and scaled to 16bits with gamma + * decoding at once + * - otherwise converted ARGB64 and gamma decoded + * 2) scale/convert etc, + * 3) and gamma encode + * + * So source data to the do_convert_to_YUV_lines() method is always + * ARGB64 + * + * Then, if output unpack format is 8bits, setup_gamma_encode() will scale + * ARGB64 down to ARGB as a part of gamma encoding, otherwise it's still + * ARGB64 + * + * Finally this to_YUV_matrix is applied. Since compute_matrix_to_YUV() + * expects [0, 1.0] range RGB as an input, scale down identity matrix + * to expected scale here, otherwise offset of the matrix would be + * very wrong + */ GST_DEBUG ("chain YUV convert"); scale = 1 << convert->pack_bits; color_matrix_scale_components (&convert->to_YUV_matrix, 1 / (float) scale, 1 / (float) scale, 1 / (float) scale); + + compute_matrix_to_YUV (convert, &convert->to_YUV_matrix, FALSE); prepare_matrix (convert, &convert->to_YUV_matrix); } convert->current_format = convert->pack_format; |