f412976eca
This avoids falling back on the VideoFrameBuffer::CropAndScale default implementation which performs ToI420. This has two major benefits: 1. We save CPU by not converting to I420 for NV12 frames. 2. We make is possible for simulcast encoders to use Scale() and be able to trust that the scaled simulcast layers have the same pixel format as the top layer, which is required by libvpx. In order to invoke NV12Buffer::CropAndScaleFrom() without introducing a circular dependency, nv12_buffer.[h/cc] is moved to the "video_frame" build target. Bug: webrtc:12595, webrtc:12469 Change-Id: I81aac5c6b3e81c49f32a7be6dc2640e6b40f7692 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/212643 Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org> Reviewed-by: Evan Shrubsole <eshr@google.com> Commit-Queue: Henrik Boström <hbos@webrtc.org> Cr-Commit-Position: refs/heads/master@{#33521}
How to write code in the api/ directory
Mostly, just follow the regular style guide, but:
- Note that
api/code is not exempt from the “.hand.ccfiles come in pairs” rule, so if you declare something inapi/path/to/foo.h, it should be defined inapi/path/to/foo.cc. - Headers in
api/should, if possible, not#includeheaders outsideapi/. It’s not always possible to avoid this, but be aware that it adds to a small mountain of technical debt that we’re trying to shrink. .ccfiles inapi/, on the other hand, are free to#includeheaders outsideapi/.
That is, the preferred way for api/ code to access non-api/ code is to call
it from a .cc file, so that users of our API headers won’t transitively
#include non-public headers.
For headers in api/ that need to refer to non-public types, forward
declarations are often a lesser evil than including non-public header files. The
usual rules still apply, though.
.cc files in api/ should preferably be kept reasonably small. If a
substantial implementation is needed, consider putting it with our non-public
code, and just call it from the api/ .cc file.