85 lines
3.5 KiB
C
85 lines
3.5 KiB
C
|
/*
|
||
|
|
* Copyright (c) 2010 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef WEBRTC_MEDIA_BASE_VIDEOADAPTER_H_
|
||
|
|
#define WEBRTC_MEDIA_BASE_VIDEOADAPTER_H_
|
||
|
|
|
||
|
|
#include "webrtc/base/constructormagic.h"
|
||
|
|
#include "webrtc/base/criticalsection.h"
|
||
|
|
#include "webrtc/base/optional.h"
|
||
|
|
#include "webrtc/media/base/videocommon.h"
|
||
|
|
|
||
|
|
namespace cricket {
|
||
|
|
|
||
|
|
// VideoAdapter adapts an input video frame to an output frame based on the
|
||
|
|
// specified input and output formats. The adaptation includes dropping frames
|
||
|
|
// to reduce frame rate and scaling frames.
|
||
|
|
// VideoAdapter is thread safe.
|
||
|
|
class VideoAdapter {
|
||
|
|
public:
|
||
|
|
VideoAdapter();
|
||
|
|
virtual ~VideoAdapter();
|
||
|
|
|
||
|
|
// Return the adapted resolution and cropping parameters given the
|
||
|
|
// input resolution. The input frame should first be cropped, then
|
||
|
|
// scaled to the final output resolution. Returns true if the frame
|
||
|
|
// should be adapted, and false if it should be dropped.
|
||
|
|
bool AdaptFrameResolution(int in_width,
|
||
|
|
int in_height,
|
||
|
|
int64_t in_timestamp_ns,
|
||
|
|
int* cropped_width,
|
||
|
|
int* cropped_height,
|
||
|
|
int* out_width,
|
||
|
|
int* out_height);
|
||
|
|
|
||
|
|
// Requests the output frame size and frame interval from
|
||
|
|
// |AdaptFrameResolution| to not be larger than |format|. Also, the input
|
||
|
|
// frame size will be cropped to match the requested aspect ratio. The
|
||
|
|
// requested aspect ratio is orientation agnostic and will be adjusted to
|
||
|
|
// maintain the input orientation, so it doesn't matter if e.g. 1280x720 or
|
||
|
|
// 720x1280 is requested.
|
||
|
|
void OnOutputFormatRequest(const VideoFormat& format);
|
||
|
|
|
||
|
|
// Requests the output frame size from |AdaptFrameResolution| to not have
|
||
|
|
// more than |max_pixel_count| pixels and have "one step" up more pixels than
|
||
|
|
// max_pixel_count_step_up.
|
||
|
|
void OnResolutionRequest(rtc::Optional<int> max_pixel_count,
|
||
|
|
rtc::Optional<int> max_pixel_count_step_up);
|
||
|
|
|
||
|
|
private:
|
||
|
|
// Determine if frame should be dropped based on input fps and requested fps.
|
||
|
|
bool KeepFrame(int64_t in_timestamp_ns);
|
||
|
|
|
||
|
|
int frames_in_; // Number of input frames.
|
||
|
|
int frames_out_; // Number of output frames.
|
||
|
|
int frames_scaled_; // Number of frames scaled.
|
||
|
|
int adaption_changes_; // Number of changes in scale factor.
|
||
|
|
int previous_width_; // Previous adapter output width.
|
||
|
|
int previous_height_; // Previous adapter output height.
|
||
|
|
// The target timestamp for the next frame based on requested format.
|
||
|
|
rtc::Optional<int64_t> next_frame_timestamp_ns_ GUARDED_BY(critical_section_);
|
||
|
|
|
||
|
|
// Max number of pixels requested via calls to OnOutputFormatRequest,
|
||
|
|
// OnResolutionRequest respectively.
|
||
|
|
// The adapted output format is the minimum of these.
|
||
|
|
rtc::Optional<VideoFormat> requested_format_ GUARDED_BY(critical_section_);
|
||
|
|
int resolution_request_max_pixel_count_ GUARDED_BY(critical_section_);
|
||
|
|
int resolution_request_max_pixel_count_step_up_ GUARDED_BY(critical_section_);
|
||
|
|
|
||
|
|
// The critical section to protect the above variables.
|
||
|
|
rtc::CriticalSection critical_section_;
|
||
|
|
|
||
|
|
RTC_DISALLOW_COPY_AND_ASSIGN(VideoAdapter);
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace cricket
|
||
|
|
|
||
|
|
#endif // WEBRTC_MEDIA_BASE_VIDEOADAPTER_H_
|