| /* |
| * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "webrtc/common_video/libyuv/include/scaler.h" |
| |
| #include <algorithm> |
| |
| // NOTE(ajm): Path provided by gyp. |
| #include "libyuv.h" // NOLINT |
| |
| namespace webrtc { |
| |
| Scaler::Scaler() |
| : method_(kScaleBox), |
| src_width_(0), |
| src_height_(0), |
| dst_width_(0), |
| dst_height_(0), |
| set_(false) {} |
| |
| Scaler::~Scaler() {} |
| |
| int Scaler::Set(int src_width, int src_height, |
| int dst_width, int dst_height, |
| VideoType src_video_type, VideoType dst_video_type, |
| ScaleMethod method) { |
| set_ = false; |
| if (src_width < 1 || src_height < 1 || dst_width < 1 || dst_height < 1) |
| return -1; |
| |
| if (!SupportedVideoType(src_video_type, dst_video_type)) |
| return -1; |
| |
| src_width_ = src_width; |
| src_height_ = src_height; |
| dst_width_ = dst_width; |
| dst_height_ = dst_height; |
| method_ = method; |
| set_ = true; |
| return 0; |
| } |
| |
| int Scaler::Scale(const VideoFrame& src_frame, VideoFrame* dst_frame) { |
| assert(dst_frame); |
| if (src_frame.IsZeroSize()) |
| return -1; |
| if (!set_) |
| return -2; |
| |
| // Making sure that destination frame is of sufficient size. |
| dst_frame->set_video_frame_buffer( |
| buffer_pool_.CreateBuffer(dst_width_, dst_height_)); |
| |
| // We want to preserve aspect ratio instead of stretching the frame. |
| // Therefore, we need to crop the source frame. Calculate the largest center |
| // aligned region of the source frame that can be used. |
| const int cropped_src_width = |
| std::min(src_width_, dst_width_ * src_height_ / dst_height_); |
| const int cropped_src_height = |
| std::min(src_height_, dst_height_ * src_width_ / dst_width_); |
| // Make sure the offsets are even to avoid rounding errors for the U/V planes. |
| const int src_offset_x = ((src_width_ - cropped_src_width) / 2) & ~1; |
| const int src_offset_y = ((src_height_ - cropped_src_height) / 2) & ~1; |
| |
| const uint8_t* y_ptr = src_frame.buffer(kYPlane) + |
| src_offset_y * src_frame.stride(kYPlane) + |
| src_offset_x; |
| const uint8_t* u_ptr = src_frame.buffer(kUPlane) + |
| src_offset_y / 2 * src_frame.stride(kUPlane) + |
| src_offset_x / 2; |
| const uint8_t* v_ptr = src_frame.buffer(kVPlane) + |
| src_offset_y / 2 * src_frame.stride(kVPlane) + |
| src_offset_x / 2; |
| |
| return libyuv::I420Scale(y_ptr, |
| src_frame.stride(kYPlane), |
| u_ptr, |
| src_frame.stride(kUPlane), |
| v_ptr, |
| src_frame.stride(kVPlane), |
| cropped_src_width, cropped_src_height, |
| dst_frame->buffer(kYPlane), |
| dst_frame->stride(kYPlane), |
| dst_frame->buffer(kUPlane), |
| dst_frame->stride(kUPlane), |
| dst_frame->buffer(kVPlane), |
| dst_frame->stride(kVPlane), |
| dst_width_, dst_height_, |
| libyuv::FilterMode(method_)); |
| } |
| |
| bool Scaler::SupportedVideoType(VideoType src_video_type, |
| VideoType dst_video_type) { |
| if (src_video_type != dst_video_type) |
| return false; |
| |
| if ((src_video_type == kI420) || (src_video_type == kIYUV) || |
| (src_video_type == kYV12)) |
| return true; |
| |
| return false; |
| } |
| |
| } // namespace webrtc |