Add scale and compare methods to VideoFrame::UpdateRect
Add tests for different UpdateRect methods as they are no longer trivial
This change will enable providing useful update rects after scaling
is done.
Bug: webrtc:11058
Change-Id: I2311dbbbb5eca5cfaf845306674e6890050f80c6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/159820
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29835}
diff --git a/api/video/video_frame.cc b/api/video/video_frame.cc
index 63902af..4f6bd86 100644
--- a/api/video/video_frame.cc
+++ b/api/video/video_frame.cc
@@ -60,6 +60,103 @@
return width == 0 && height == 0;
}
+VideoFrame::UpdateRect VideoFrame::UpdateRect::ScaleWithFrame(
+ int frame_width,
+ int frame_height,
+ int crop_x,
+ int crop_y,
+ int crop_width,
+ int crop_height,
+ int scaled_width,
+ int scaled_height) const {
+ RTC_DCHECK_GT(frame_width, 0);
+ RTC_DCHECK_GT(frame_height, 0);
+
+ RTC_DCHECK_GT(crop_width, 0);
+ RTC_DCHECK_GT(crop_height, 0);
+
+ RTC_DCHECK_LE(crop_width + crop_x, frame_width);
+ RTC_DCHECK_LE(crop_height + crop_y, frame_height);
+
+ RTC_DCHECK_GT(scaled_width, 0);
+ RTC_DCHECK_GT(scaled_height, 0);
+
+ // Check if update rect is out of the cropped area.
+ if (offset_x + width < crop_x || offset_x > crop_x + crop_width ||
+ offset_y + height < crop_y || offset_y > crop_y + crop_width) {
+ return {0, 0, 0, 0};
+ }
+
+ int x = offset_x - crop_x;
+ int w = width;
+ if (x < 0) {
+ w += x;
+ x = 0;
+ }
+ int y = offset_y - crop_y;
+ int h = height;
+ if (y < 0) {
+ h += y;
+ y = 0;
+ }
+
+ // Lower corner is rounded down.
+ x = x * scaled_width / crop_width;
+ y = y * scaled_height / crop_height;
+ // Upper corner is rounded up.
+ w = (w * scaled_width + crop_width - 1) / crop_width;
+ h = (h * scaled_height + crop_height - 1) / crop_height;
+
+ // Round to full 2x2 blocks due to possible subsampling in the pixel data.
+ if (x % 2) {
+ --x;
+ ++w;
+ }
+ if (y % 2) {
+ --y;
+ ++h;
+ }
+ if (w % 2) {
+ ++w;
+ }
+ if (h % 2) {
+ ++h;
+ }
+
+ // Expand the update rect by 2 pixels in each direction to include any
+ // possible scaling artifacts.
+ if (scaled_width != crop_width || scaled_height != crop_height) {
+ if (x > 0) {
+ x -= 2;
+ w += 2;
+ }
+ if (y > 0) {
+ y -= 2;
+ h += 2;
+ }
+ w += 2;
+ h += 2;
+ }
+
+ // Ensure update rect is inside frame dimensions.
+ if (x + w > scaled_width) {
+ w = scaled_width - x;
+ }
+ if (y + h > scaled_height) {
+ h = scaled_height - y;
+ }
+ RTC_DCHECK_GE(w, 0);
+ RTC_DCHECK_GE(h, 0);
+ if (w == 0 || h == 0) {
+ w = 0;
+ h = 0;
+ x = 0;
+ y = 0;
+ }
+
+ return {x, y, w, h};
+}
+
VideoFrame::Builder::Builder() = default;
VideoFrame::Builder::~Builder() = default;
