Android: Add support for cropping textures
BUG=b/28622232
R=glaznev@webrtc.org, nisse@webrtc.org
Review URL: https://codereview.webrtc.org/1965953003 .
Cr-Commit-Position: refs/heads/master@{#12720}
diff --git a/webrtc/api/java/jni/native_handle_impl.cc b/webrtc/api/java/jni/native_handle_impl.cc
index 1990828..1f180ad 100644
--- a/webrtc/api/java/jni/native_handle_impl.cc
+++ b/webrtc/api/java/jni/native_handle_impl.cc
@@ -59,6 +59,37 @@
}
}
+// Calculates result = a * b, in column-major order.
+void MultiplyMatrix(const float a[16], const float b[16], float result[16]) {
+ for (int i = 0; i < 4; ++i) {
+ for (int j = 0; j < 4; ++j) {
+ float sum = 0;
+ for (int k = 0; k < 4; ++k) {
+ sum += a[k * 4 + j] * b[i * 4 + k];
+ }
+ result[i * 4 + j] = sum;
+ }
+ }
+}
+
+// Center crop by keeping xFraction of the width and yFraction of the height,
+// so e.g. cropping from 640x480 to 640x360 would use
+// xFraction=1, yFraction=360/480.
+void CropMatrix(float a[16], float xFraction, float yFraction) {
+ // Move cropped area to the center of the frame by offsetting half the
+ // removed area.
+ const float xOffset = (1 - xFraction) / 2;
+ const float yOffset = (1 - yFraction) / 2;
+ const float crop_matrix[16] = {
+ xFraction, 0, 0, 0,
+ 0, yFraction, 0, 0,
+ 0, 0, 1, 0,
+ xOffset, yOffset, 0, 1};
+ float mul_result[16];
+ MultiplyMatrix(crop_matrix, a, mul_result);
+ memcpy(a, mul_result, sizeof(mul_result));
+}
+
} // anonymouse namespace
namespace webrtc_jni {
@@ -146,15 +177,18 @@
}
rtc::scoped_refptr<AndroidTextureBuffer>
-AndroidTextureBuffer::ScaleAndRotate(int dst_widht,
- int dst_height,
- webrtc::VideoRotation rotation) {
- if (width() == dst_widht && height() == dst_height &&
+AndroidTextureBuffer::CropScaleAndRotate(int cropped_width,
+ int cropped_height,
+ int dst_width,
+ int dst_height,
+ webrtc::VideoRotation rotation) {
+ if (cropped_width == dst_width && cropped_height == dst_height &&
+ width() == dst_width && height() == dst_height &&
rotation == webrtc::kVideoRotation_0) {
return this;
}
- int rotated_width = (rotation % 180 == 0) ? dst_widht : dst_height;
- int rotated_height = (rotation % 180 == 0) ? dst_height : dst_widht;
+ int rotated_width = (rotation % 180 == 0) ? dst_width : dst_height;
+ int rotated_height = (rotation % 180 == 0) ? dst_height : dst_width;
// Here we use Bind magic to add a reference count to |this| until the newly
// created AndroidTextureBuffer is destructed
@@ -163,6 +197,11 @@
rotated_width, rotated_height, native_handle_,
surface_texture_helper_, rtc::KeepRefUntilDone(this)));
+ if (cropped_width != width() || cropped_height != height()) {
+ CropMatrix(buffer->native_handle_.sampling_matrix,
+ cropped_width / static_cast<float>(width()),
+ cropped_height / static_cast<float>(height()));
+ }
RotateMatrix(buffer->native_handle_.sampling_matrix, rotation);
return buffer;
}