Hello,
I am using Voukoder Pro 3.2.2 with VEGAS Pro 22 to create H.264 MP4 files for cable TV broadcast.
I have a question about how BT.709 color metadata is written into the H.264 output.
With the old free version of Voukoder, my H.264 output contained all three BT.709 color parameters:
Color range: Limited
Color primaries: BT.709
Transfer characteristics: BT.709
Matrix coefficients: BT.709
With Voukoder Pro 3.2.2, I can now successfully create the H.264 file, but only the following color information is present:
Color range: Limited
Matrix coefficients: BT.709
The following two parameters are missing:
Color primaries: BT.709
Transfer characteristics: BT.709
This is not only a MediaInfo display issue. I have checked the same output using:
MediaInfo
MediaInfo XML
ffprobe
MediaTrace
and all of them show the same result: BT.709 matrix coefficients are present, but BT.709 color primaries and transfer characteristics are not present.
The resulting video is:
1920 × 1080
59.940 fps
Progressive
YUV 4:2:0 8-bit
H.264 High@L4.2
Limited range
Matrix coefficients: BT.709
My goal is to produce a standard H.264/AVC BT.709 file for cable TV delivery with the following color metadata explicitly present:
color_range = TV/Limited
color_primaries = BT.709
transfer_characteristics = BT.709
matrix_coefficients = BT.709
I have tried using Voukoder's video input color settings and also tested setparams and other filter configurations. However, I would prefer to set the correct metadata directly through the encoder/settings rather than use a filter that unnecessarily modifies the video.
My questions are:
Does Voukoder Pro 3.2.2 write color_primaries, transfer_characteristics, and matrix_coefficients to the H.264 VUI in the same way as the old free Voukoder?
What is the correct Voukoder Pro 3.2.2 configuration for libx264 to explicitly write all three BT.709 parameters?
If this is controlled by x264 parameters, should the equivalent settings be something like:
colorprim=bt709
transfer=bt709
colormatrix=bt709
or does Voukoder Pro handle these parameters differently?
Is the absence of color_primaries and transfer_characteristics in the output expected behavior in Voukoder Pro 3.2.2, or could this be a bug/regression compared with the old free Voukoder?
I am mainly trying to understand how Voukoder Pro 3.2.2 handles H.264 BT.709 VUI metadata, because the actual video encoding is working correctly.
I previously used the old free Voukoder with VEGAS Pro 20, where my H.264 files contained all three BT.709 parameters. I am now using Voukoder Pro 3.2.2 with VEGAS Pro 22, and the same type of H.264 output contains only the BT.709 matrix coefficients.
Could the difference be related to how VEGAS Pro 22 passes color metadata to Voukoder Pro 3.2.2, or should Voukoder Pro explicitly set all three H.264 VUI parameters independently of the metadata received from VEGAS?
Best regards,
John
