In the vt_h264_video_info function, the format of the video to be encoded is
always being set to VIDEO_FORMAT_NV12, dispite the presence of code to set
the video format to VIDEO_FORMAT_I420 or VIDEO_FORMAT_I444. This commit fixes
that function to respect the video format choice of the user.
In addition, whilst testing this fix initially, I also discovered that the
4:4:4 colour format is not supported by the VideoToolbox H264 encoder.
Looking at the VideoToolbox code in ffmpeg as a reference, the ffmpeg code
errors out if a color format other than NV12 or I420 is set. Therefore, this
commit also logs a warning about I444 not being supported, and uses the NV12
default.
The fullrange variable is used to set appropriate video format information in
vt_h264_video_info. Set fullrange first so the video format data is correct in
all cases.
Adds a VideoToolbox based H264 encoder for OSX, which most notably
allows the use of hardware encoding (Quicksync).
NOTES:
- Hardware encoding is handled by Apple itself internally. The plugin
itself has little control over many details due to the way that Apple
designed the VideoToolbox interface. Generally however, quicksync is
used if available on the CPU, and quicksync is almost always available
due to the fact that macs are exclusively Intel.
- The VideoToolbox does not seem to implement CBR, so it won't be
available. These encoders are generally not recommended for
streaming.
Marvin Scholz
Gol-D-Ace
Jim
Luke Yelavich
dodgepong
kc5nra