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/*
* Copyright 2017 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.
*/
#import "ARDCaptureController.h"
#import "sdk/objc/base/RTCLogging.h"
#import "ARDSettingsModel.h"
const Float64 kFramerateLimit = 30.0;
@implementation ARDCaptureController {
RTC_OBJC_TYPE(RTCCameraVideoCapturer) * _capturer;
ARDSettingsModel *_settings;
BOOL _usingFrontCamera;
}
- (instancetype)initWithCapturer:
(RTC_OBJC_TYPE(RTCCameraVideoCapturer) *)capturer
settings:(ARDSettingsModel *)settings {
self = [super init];
if (self) {
_capturer = capturer;
_settings = settings;
_usingFrontCamera = YES;
}
return self;
}
- (void)startCapture {
[self startCapture:nil];
}
- (void)startCapture:(void (^)(NSError *))completion {
AVCaptureDevicePosition position = _usingFrontCamera ?
AVCaptureDevicePositionFront :
AVCaptureDevicePositionBack;
AVCaptureDevice *device = [self findDeviceForPosition:position];
AVCaptureDeviceFormat *format = [self selectFormatForDevice:device];
if (format == nil) {
RTCLogError(@"No valid formats for device %@", device);
NSAssert(NO, @"");
return;
}
NSInteger fps = [self selectFpsForFormat:format];
[_capturer startCaptureWithDevice:device
format:format
fps:fps
completionHandler:completion];
}
- (void)stopCapture {
[_capturer stopCapture];
}
- (void)switchCamera {
_usingFrontCamera = !_usingFrontCamera;
[self startCapture:nil];
}
- (void)switchCamera:(void (^)(NSError *))completion {
_usingFrontCamera = !_usingFrontCamera;
[self startCapture:completion];
}
#pragma mark - Private
- (AVCaptureDevice *)findDeviceForPosition:(AVCaptureDevicePosition)position {
NSArray<AVCaptureDevice *> *captureDevices =
[RTC_OBJC_TYPE(RTCCameraVideoCapturer) captureDevices];
for (AVCaptureDevice *device in captureDevices) {
if (device.position == position) {
return device;
}
}
return captureDevices[0];
}
- (AVCaptureDeviceFormat *)selectFormatForDevice:(AVCaptureDevice *)device {
NSArray<AVCaptureDeviceFormat *> *formats =
[RTC_OBJC_TYPE(RTCCameraVideoCapturer) supportedFormatsForDevice:device];
int targetWidth = [_settings currentVideoResolutionWidthFromStore];
int targetHeight = [_settings currentVideoResolutionHeightFromStore];
AVCaptureDeviceFormat *selectedFormat = nil;
int currentDiff = INT_MAX;
for (AVCaptureDeviceFormat *format in formats) {
CMVideoDimensions dimension =
CMVideoFormatDescriptionGetDimensions(format.formatDescription);
FourCharCode pixelFormat =
CMFormatDescriptionGetMediaSubType(format.formatDescription);
int diff = abs(targetWidth - dimension.width) +
abs(targetHeight - dimension.height);
if (diff < currentDiff) {
selectedFormat = format;
currentDiff = diff;
} else if (diff == currentDiff &&
pixelFormat == [_capturer preferredOutputPixelFormat]) {
selectedFormat = format;
}
}
return selectedFormat;
}
- (NSInteger)selectFpsForFormat:(AVCaptureDeviceFormat *)format {
Float64 maxSupportedFramerate = 0;
for (AVFrameRateRange *fpsRange in format.videoSupportedFrameRateRanges) {
maxSupportedFramerate = fmax(maxSupportedFramerate, fpsRange.maxFrameRate);
}
return fmin(maxSupportedFramerate, kFramerateLimit);
}
@end
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