gstreamer/sys/applemedia/avfvideosrc.m

1448 lines
42 KiB
Objective-C

/*
* Copyright (C) 2010 Ole André Vadla Ravnås <oleavr@soundrop.com>
* Copyright (C) 2016 Alessandro Decina <twi@centricular.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "avfvideosrc.h"
#include "glcontexthelper.h"
#import <AVFoundation/AVFoundation.h>
#if !HAVE_IOS
#import <AppKit/AppKit.h>
#endif
#include <gst/video/video.h>
#include <gst/gl/gstglcontext.h>
#include "coremediabuffer.h"
#include "videotexturecache.h"
#define DEFAULT_DEVICE_INDEX -1
#define DEFAULT_DO_STATS FALSE
#define DEVICE_FPS_N 25
#define DEVICE_FPS_D 1
#define BUFFER_QUEUE_SIZE 2
GST_DEBUG_CATEGORY (gst_avf_video_src_debug);
#define GST_CAT_DEFAULT gst_avf_video_src_debug
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (
#if !HAVE_IOS
GST_VIDEO_CAPS_MAKE_WITH_FEATURES
(GST_CAPS_FEATURE_MEMORY_GL_MEMORY,
"UYVY") ", "
"texture-target = " GST_GL_TEXTURE_TARGET_RECTANGLE_STR ";"
#else
GST_VIDEO_CAPS_MAKE_WITH_FEATURES
(GST_CAPS_FEATURE_MEMORY_GL_MEMORY,
"NV12") ", "
"texture-target = " GST_GL_TEXTURE_TARGET_2D_STR "; "
#endif
"video/x-raw, "
"format = (string) { NV12, UYVY, YUY2 }, "
"framerate = " GST_VIDEO_FPS_RANGE ", "
"width = " GST_VIDEO_SIZE_RANGE ", "
"height = " GST_VIDEO_SIZE_RANGE "; "
"video/x-raw, "
"format = (string) BGRA, "
"framerate = " GST_VIDEO_FPS_RANGE ", "
"width = " GST_VIDEO_SIZE_RANGE ", "
"height = " GST_VIDEO_SIZE_RANGE "; "
));
typedef enum _QueueState {
NO_BUFFERS = 1,
HAS_BUFFER_OR_STOP_REQUEST,
} QueueState;
#define gst_avf_video_src_parent_class parent_class
G_DEFINE_TYPE (GstAVFVideoSrc, gst_avf_video_src, GST_TYPE_PUSH_SRC);
@interface GstAVFVideoSrcImpl : NSObject <AVCaptureVideoDataOutputSampleBufferDelegate> {
GstElement *element;
GstBaseSrc *baseSrc;
GstPushSrc *pushSrc;
gint deviceIndex;
BOOL doStats;
AVCaptureSession *session;
AVCaptureInput *input;
AVCaptureVideoDataOutput *output;
AVCaptureDevice *device;
AVCaptureConnection *connection;
CMClockRef inputClock;
dispatch_queue_t mainQueue;
dispatch_queue_t workerQueue;
NSConditionLock *bufQueueLock;
NSMutableArray *bufQueue;
BOOL stopRequest;
GstCaps *caps;
GstVideoFormat format;
gint width, height;
GstClockTime latency;
guint64 offset;
GstClockTime lastSampling;
guint count;
gint fps;
BOOL captureScreen;
BOOL captureScreenCursor;
BOOL captureScreenMouseClicks;
BOOL useVideoMeta;
GstGLContextHelper *ctxh;
GstVideoTextureCache *textureCache;
}
- (id)init;
- (id)initWithSrc:(GstPushSrc *)src;
- (void)finalize;
@property int deviceIndex;
@property BOOL doStats;
@property int fps;
@property BOOL captureScreen;
@property BOOL captureScreenCursor;
@property BOOL captureScreenMouseClicks;
- (BOOL)openScreenInput;
- (BOOL)openDeviceInput;
- (BOOL)openDevice;
- (void)closeDevice;
- (GstVideoFormat)getGstVideoFormat:(NSNumber *)pixel_format;
#if !HAVE_IOS
- (CGDirectDisplayID)getDisplayIdFromDeviceIndex;
#endif
- (GstCaps *)getDeviceCaps;
- (BOOL)setDeviceCaps:(GstVideoInfo *)info;
- (BOOL)getSessionPresetCaps:(GstCaps *)result;
- (BOOL)setSessionPresetCaps:(GstVideoInfo *)info;
- (GstCaps *)getCaps;
- (BOOL)setCaps:(GstCaps *)new_caps;
- (BOOL)start;
- (BOOL)stop;
- (BOOL)unlock;
- (BOOL)unlockStop;
- (BOOL)query:(GstQuery *)query;
- (void)setContext:(GstContext *)context;
- (GstStateChangeReturn)changeState:(GstStateChange)transition;
- (GstFlowReturn)create:(GstBuffer **)buf;
- (GstCaps *)fixate:(GstCaps *)caps;
- (BOOL)decideAllocation:(GstQuery *)query;
- (void)updateStatistics;
- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
fromConnection:(AVCaptureConnection *)connection;
@end
@implementation GstAVFVideoSrcImpl
@synthesize deviceIndex, doStats, fps, captureScreen,
captureScreenCursor, captureScreenMouseClicks;
- (id)init
{
return [self initWithSrc:NULL];
}
- (id)initWithSrc:(GstPushSrc *)src
{
if ((self = [super init])) {
element = GST_ELEMENT_CAST (src);
baseSrc = GST_BASE_SRC_CAST (src);
pushSrc = src;
deviceIndex = DEFAULT_DEVICE_INDEX;
captureScreen = NO;
captureScreenCursor = NO;
captureScreenMouseClicks = NO;
useVideoMeta = NO;
textureCache = NULL;
ctxh = gst_gl_context_helper_new (element);
mainQueue =
dispatch_queue_create ("org.freedesktop.gstreamer.avfvideosrc.main", NULL);
workerQueue =
dispatch_queue_create ("org.freedesktop.gstreamer.avfvideosrc.output", NULL);
gst_base_src_set_live (baseSrc, TRUE);
gst_base_src_set_format (baseSrc, GST_FORMAT_TIME);
}
return self;
}
- (void)finalize
{
dispatch_release (mainQueue);
mainQueue = NULL;
dispatch_release (workerQueue);
workerQueue = NULL;
[super finalize];
}
- (BOOL)openDeviceInput
{
NSString *mediaType = AVMediaTypeVideo;
NSError *err;
if (deviceIndex == DEFAULT_DEVICE_INDEX) {
device = [AVCaptureDevice defaultDeviceWithMediaType:mediaType];
if (device == nil) {
GST_ELEMENT_ERROR (element, RESOURCE, NOT_FOUND,
("No video capture devices found"), (NULL));
return NO;
}
} else {
NSArray *devices = [AVCaptureDevice devicesWithMediaType:mediaType];
if (deviceIndex >= [devices count]) {
GST_ELEMENT_ERROR (element, RESOURCE, NOT_FOUND,
("Invalid video capture device index"), (NULL));
return NO;
}
device = [devices objectAtIndex:deviceIndex];
}
g_assert (device != nil);
[device retain];
GST_INFO ("Opening '%s'", [[device localizedName] UTF8String]);
input = [AVCaptureDeviceInput deviceInputWithDevice:device
error:&err];
if (input == nil) {
GST_ELEMENT_ERROR (element, RESOURCE, BUSY,
("Failed to open device: %s",
[[err localizedDescription] UTF8String]),
(NULL));
[device release];
device = nil;
return NO;
}
[input retain];
return YES;
}
- (BOOL)openScreenInput
{
#if HAVE_IOS
return NO;
#else
CGDirectDisplayID displayId;
GST_DEBUG_OBJECT (element, "Opening screen input");
displayId = [self getDisplayIdFromDeviceIndex];
if (displayId == 0)
return NO;
AVCaptureScreenInput *screenInput =
[[AVCaptureScreenInput alloc] initWithDisplayID:displayId];
@try {
[screenInput setValue:[NSNumber numberWithBool:captureScreenCursor]
forKey:@"capturesCursor"];
} @catch (NSException *exception) {
if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
GST_WARNING ("An unexpected error occured: %s",
[[exception reason] UTF8String]);
}
GST_WARNING ("Capturing cursor is only supported in OS X >= 10.8");
}
screenInput.capturesMouseClicks = captureScreenMouseClicks;
input = screenInput;
[input retain];
return YES;
#endif
}
- (BOOL)openDevice
{
BOOL success = NO, *successPtr = &success;
GST_DEBUG_OBJECT (element, "Opening device");
dispatch_sync (mainQueue, ^{
BOOL ret;
if (captureScreen)
ret = [self openScreenInput];
else
ret = [self openDeviceInput];
if (!ret)
return;
output = [[AVCaptureVideoDataOutput alloc] init];
[output setSampleBufferDelegate:self
queue:workerQueue];
output.alwaysDiscardsLateVideoFrames = YES;
output.videoSettings = nil; /* device native format */
session = [[AVCaptureSession alloc] init];
[session addInput:input];
[session addOutput:output];
/* retained by session */
connection = [[output connections] firstObject];
inputClock = ((AVCaptureInputPort *)connection.inputPorts[0]).clock;
*successPtr = YES;
});
GST_DEBUG_OBJECT (element, "Opening device %s", success ? "succeed" : "failed");
return success;
}
- (void)closeDevice
{
GST_DEBUG_OBJECT (element, "Closing device");
dispatch_sync (mainQueue, ^{
g_assert (![session isRunning]);
connection = nil;
inputClock = nil;
[session removeInput:input];
[session removeOutput:output];
[session release];
session = nil;
[input release];
input = nil;
[output release];
output = nil;
if (!captureScreen) {
[device release];
device = nil;
}
if (caps)
gst_caps_unref (caps);
caps = NULL;
});
}
#define GST_AVF_CAPS_NEW(format, w, h, fps_n, fps_d) \
(gst_caps_new_simple ("video/x-raw", \
"width", G_TYPE_INT, w, \
"height", G_TYPE_INT, h, \
"format", G_TYPE_STRING, gst_video_format_to_string (format), \
"framerate", GST_TYPE_FRACTION, (fps_n), (fps_d), \
NULL))
#define GST_AVF_FPS_RANGE_CAPS_NEW(format, w, h, min_fps_n, min_fps_d, max_fps_n, max_fps_d) \
(gst_caps_new_simple ("video/x-raw", \
"width", G_TYPE_INT, w, \
"height", G_TYPE_INT, h, \
"format", G_TYPE_STRING, gst_video_format_to_string (format), \
"framerate", GST_TYPE_FRACTION_RANGE, (min_fps_n), (min_fps_d), (max_fps_n), (max_fps_d), \
NULL))
- (GstVideoFormat)getGstVideoFormat:(NSNumber *)pixel_format
{
GstVideoFormat gst_format = GST_VIDEO_FORMAT_UNKNOWN;
switch ([pixel_format integerValue]) {
case kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange: /* 420v */
gst_format = GST_VIDEO_FORMAT_NV12;
break;
case kCVPixelFormatType_422YpCbCr8: /* 2vuy */
gst_format = GST_VIDEO_FORMAT_UYVY;
break;
case kCVPixelFormatType_32BGRA: /* BGRA */
gst_format = GST_VIDEO_FORMAT_BGRA;
break;
case kCVPixelFormatType_422YpCbCr8_yuvs: /* yuvs */
gst_format = GST_VIDEO_FORMAT_YUY2;
break;
default:
GST_LOG_OBJECT (element, "Pixel format %s is not handled by avfvideosrc",
[[pixel_format stringValue] UTF8String]);
break;
}
return gst_format;
}
#if !HAVE_IOS
- (CGDirectDisplayID)getDisplayIdFromDeviceIndex
{
NSDictionary *description;
NSNumber *displayId;
NSArray *screens = [NSScreen screens];
if (deviceIndex == DEFAULT_DEVICE_INDEX)
return kCGDirectMainDisplay;
if (deviceIndex >= [screens count]) {
GST_ELEMENT_ERROR (element, RESOURCE, NOT_FOUND,
("Invalid screen capture device index"), (NULL));
return 0;
}
description = [[screens objectAtIndex:deviceIndex] deviceDescription];
displayId = [description objectForKey:@"NSScreenNumber"];
return [displayId unsignedIntegerValue];
}
#endif
- (GstCaps *)getDeviceCaps
{
NSArray *formats = [device valueForKey:@"formats"];
NSArray *pixel_formats = output.availableVideoCVPixelFormatTypes;
GstCaps *result_caps, *result_gl_caps;
#if !HAVE_IOS
GstVideoFormat gl_format = GST_VIDEO_FORMAT_UYVY;
#else
GstVideoFormat gl_format = GST_VIDEO_FORMAT_NV12;
#endif
GST_DEBUG_OBJECT (element, "Getting device caps");
result_caps = gst_caps_new_empty ();
result_gl_caps = gst_caps_new_empty ();
/* Do not use AVCaptureDeviceFormat or AVFrameRateRange only
* available in iOS >= 7.0. We use a dynamic approach with key-value
* coding or performSelector */
for (NSObject *f in [formats reverseObjectEnumerator]) {
CMFormatDescriptionRef formatDescription;
CMVideoDimensions dimensions;
/* formatDescription can't be retrieved with valueForKey so use a selector here */
formatDescription = (CMFormatDescriptionRef) [f performSelector:@selector(formatDescription)];
dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);
for (NSObject *rate in [f valueForKey:@"videoSupportedFrameRateRanges"]) {
int min_fps_n, min_fps_d, max_fps_n, max_fps_d;
gdouble min_fps, max_fps;
[[rate valueForKey:@"minFrameRate"] getValue:&min_fps];
gst_util_double_to_fraction (min_fps, &min_fps_n, &min_fps_d);
[[rate valueForKey:@"maxFrameRate"] getValue:&max_fps];
gst_util_double_to_fraction (max_fps, &max_fps_n, &max_fps_d);
for (NSNumber *pixel_format in pixel_formats) {
GstVideoFormat gst_format = [self getGstVideoFormat:pixel_format];
if (gst_format != GST_VIDEO_FORMAT_UNKNOWN) {
if (min_fps != max_fps)
gst_caps_append (result_caps, GST_AVF_FPS_RANGE_CAPS_NEW (gst_format, dimensions.width, dimensions.height, min_fps_n, min_fps_d, max_fps_n, max_fps_d));
else
gst_caps_append (result_caps, GST_AVF_CAPS_NEW (gst_format, dimensions.width, dimensions.height, max_fps_n, max_fps_d));
}
if (gst_format == gl_format) {
GstCaps *gl_caps;
if (min_fps != max_fps) {
gl_caps = GST_AVF_FPS_RANGE_CAPS_NEW (gl_format,
dimensions.width, dimensions.height,
min_fps_n, min_fps_d,
max_fps_n, max_fps_d);
} else {
gl_caps = GST_AVF_CAPS_NEW (gl_format,
dimensions.width, dimensions.height,
max_fps_n, max_fps_d);
}
gst_caps_set_features (gl_caps, 0,
gst_caps_features_new (GST_CAPS_FEATURE_MEMORY_GL_MEMORY,
NULL));
gst_caps_set_simple (gl_caps,
"texture-target", G_TYPE_STRING,
#if !HAVE_IOS
GST_GL_TEXTURE_TARGET_RECTANGLE_STR,
#else
GST_GL_TEXTURE_TARGET_2D_STR,
#endif
NULL);
gst_caps_append (result_gl_caps, gl_caps);
}
}
}
}
result_gl_caps = gst_caps_simplify (gst_caps_merge (result_gl_caps, result_caps));
GST_DEBUG_OBJECT (element, "Device returned the following caps %" GST_PTR_FORMAT, result_gl_caps);
return result_gl_caps;
}
- (BOOL)setDeviceCaps:(GstVideoInfo *)info
{
double framerate;
gboolean found_format = FALSE, found_framerate = FALSE;
NSArray *formats = [device valueForKey:@"formats"];
gst_util_fraction_to_double (info->fps_n, info->fps_d, &framerate);
GST_DEBUG_OBJECT (element, "Setting device caps");
if ([device lockForConfiguration:NULL] == YES) {
for (NSObject *f in formats) {
CMFormatDescriptionRef formatDescription;
CMVideoDimensions dimensions;
formatDescription = (CMFormatDescriptionRef) [f performSelector:@selector(formatDescription)];
dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);
if (dimensions.width == info->width && dimensions.height == info->height) {
found_format = TRUE;
[device setValue:f forKey:@"activeFormat"];
for (NSObject *rate in [f valueForKey:@"videoSupportedFrameRateRanges"]) {
gdouble min_frame_rate, max_frame_rate;
[[rate valueForKey:@"minFrameRate"] getValue:&min_frame_rate];
[[rate valueForKey:@"maxFrameRate"] getValue:&max_frame_rate];
if ((framerate >= min_frame_rate - 0.00001) &&
(framerate <= max_frame_rate + 0.00001)) {
NSValue *frame_duration_value;
found_framerate = TRUE;
if (min_frame_rate == max_frame_rate) {
/* on mac we get tight ranges and an exception is raised if the
* frame duration doesn't match the one reported in the range to
* the last decimal point
*/
frame_duration_value = [rate valueForKey:@"minFrameDuration"];
} else {
// Invert fps_n and fps_d to get frame duration value and timescale (or numerator and denominator)
frame_duration_value = [NSValue valueWithCMTime:CMTimeMake (info->fps_d, info->fps_n)];
}
[device setValue:frame_duration_value forKey:@"activeVideoMinFrameDuration"];
@try {
/* Only available on OSX >= 10.8 and iOS >= 7.0 */
[device setValue:frame_duration_value forKey:@"activeVideoMaxFrameDuration"];
} @catch (NSException *exception) {
if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
GST_WARNING ("An unexcepted error occured: %s",
[exception.reason UTF8String]);
}
}
break;
}
}
}
}
if (!found_format) {
GST_WARNING ("Unsupported capture dimensions %dx%d", info->width, info->height);
return NO;
}
if (!found_framerate) {
GST_WARNING ("Unsupported capture framerate %d/%d", info->fps_n, info->fps_d);
return NO;
}
} else {
GST_WARNING ("Couldn't lock device for configuration");
return NO;
}
return YES;
}
- (BOOL)getSessionPresetCaps:(GstCaps *)result
{
NSArray *pixel_formats = output.availableVideoCVPixelFormatTypes;
for (NSNumber *pixel_format in pixel_formats) {
GstVideoFormat gst_format = [self getGstVideoFormat:pixel_format];
if (gst_format == GST_VIDEO_FORMAT_UNKNOWN)
continue;
#if HAVE_IOS
if ([session canSetSessionPreset:AVCaptureSessionPreset1920x1080])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 1920, 1080, DEVICE_FPS_N, DEVICE_FPS_D));
#endif
if ([session canSetSessionPreset:AVCaptureSessionPreset1280x720])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 1280, 720, DEVICE_FPS_N, DEVICE_FPS_D));
if ([session canSetSessionPreset:AVCaptureSessionPreset640x480])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 640, 480, DEVICE_FPS_N, DEVICE_FPS_D));
if ([session canSetSessionPreset:AVCaptureSessionPresetMedium])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 480, 360, DEVICE_FPS_N, DEVICE_FPS_D));
if ([session canSetSessionPreset:AVCaptureSessionPreset352x288])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 352, 288, DEVICE_FPS_N, DEVICE_FPS_D));
if ([session canSetSessionPreset:AVCaptureSessionPresetLow])
gst_caps_append (result, GST_AVF_CAPS_NEW (gst_format, 192, 144, DEVICE_FPS_N, DEVICE_FPS_D));
}
GST_LOG_OBJECT (element, "Session presets returned the following caps %" GST_PTR_FORMAT, result);
return YES;
}
- (BOOL)setSessionPresetCaps:(GstVideoInfo *)info;
{
GST_DEBUG_OBJECT (element, "Setting session presset caps");
if ([device lockForConfiguration:NULL] != YES) {
GST_WARNING ("Couldn't lock device for configuration");
return NO;
}
switch (info->width) {
case 192:
session.sessionPreset = AVCaptureSessionPresetLow;
break;
case 352:
session.sessionPreset = AVCaptureSessionPreset352x288;
break;
case 480:
session.sessionPreset = AVCaptureSessionPresetMedium;
break;
case 640:
session.sessionPreset = AVCaptureSessionPreset640x480;
break;
case 1280:
session.sessionPreset = AVCaptureSessionPreset1280x720;
break;
#if HAVE_IOS
case 1920:
session.sessionPreset = AVCaptureSessionPreset1920x1080;
break;
#endif
default:
GST_WARNING ("Unsupported capture dimensions %dx%d", info->width, info->height);
return NO;
}
return YES;
}
- (GstCaps *)getCaps
{
GstCaps *result;
NSArray *pixel_formats;
if (session == nil)
return NULL; /* BaseSrc will return template caps */
result = gst_caps_new_empty ();
pixel_formats = output.availableVideoCVPixelFormatTypes;
if (captureScreen) {
#if !HAVE_IOS
CGRect rect = CGDisplayBounds ([self getDisplayIdFromDeviceIndex]);
for (NSNumber *pixel_format in pixel_formats) {
GstVideoFormat gst_format = [self getGstVideoFormat:pixel_format];
if (gst_format != GST_VIDEO_FORMAT_UNKNOWN)
gst_caps_append (result, gst_caps_new_simple ("video/x-raw",
"width", G_TYPE_INT, (int)rect.size.width,
"height", G_TYPE_INT, (int)rect.size.height,
"format", G_TYPE_STRING, gst_video_format_to_string (gst_format),
NULL));
}
#else
GST_WARNING ("Screen capture is not supported by iOS");
#endif
return result;
}
@try {
result = gst_caps_merge (result, [self getDeviceCaps]);
} @catch (NSException *exception) {
if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
GST_WARNING ("An unexcepted error occured: %s", [exception.reason UTF8String]);
return result;
}
/* Fallback on session presets API for iOS < 7.0 */
[self getSessionPresetCaps:result];
}
return result;
}
- (BOOL)setCaps:(GstCaps *)new_caps
{
GstVideoInfo info;
BOOL success = YES, *successPtr = &success;
gst_video_info_init (&info);
gst_video_info_from_caps (&info, new_caps);
width = info.width;
height = info.height;
format = info.finfo->format;
latency = gst_util_uint64_scale (GST_SECOND, info.fps_d, info.fps_n);
dispatch_sync (mainQueue, ^{
int newformat;
if (captureScreen) {
#if !HAVE_IOS
AVCaptureScreenInput *screenInput = (AVCaptureScreenInput *)input;
screenInput.minFrameDuration = CMTimeMake(info.fps_d, info.fps_n);
#else
GST_WARNING ("Screen capture is not supported by iOS");
*successPtr = NO;
return;
#endif
} else {
@try {
/* formats and activeFormat keys are only available on OSX >= 10.7 and iOS >= 7.0 */
*successPtr = [self setDeviceCaps:(GstVideoInfo *)&info];
if (*successPtr != YES)
return;
} @catch (NSException *exception) {
if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
GST_WARNING ("An unexcepted error occured: %s", [exception.reason UTF8String]);
*successPtr = NO;
return;
}
/* Fallback on session presets API for iOS < 7.0 */
*successPtr = [self setSessionPresetCaps:(GstVideoInfo *)&info];
if (*successPtr != YES)
return;
}
}
switch (format) {
case GST_VIDEO_FORMAT_NV12:
newformat = kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange;
break;
case GST_VIDEO_FORMAT_UYVY:
newformat = kCVPixelFormatType_422YpCbCr8;
break;
case GST_VIDEO_FORMAT_YUY2:
newformat = kCVPixelFormatType_422YpCbCr8_yuvs;
break;
case GST_VIDEO_FORMAT_BGRA:
newformat = kCVPixelFormatType_32BGRA;
break;
default:
*successPtr = NO;
GST_WARNING ("Unsupported output format %s",
gst_video_format_to_string (format));
return;
}
GST_INFO_OBJECT (element,
"width: %d height: %d format: %s", width, height,
gst_video_format_to_string (format));
output.videoSettings = [NSDictionary
dictionaryWithObject:[NSNumber numberWithInt:newformat]
forKey:(NSString*)kCVPixelBufferPixelFormatTypeKey];
gst_caps_replace (&caps, new_caps);
GST_INFO_OBJECT (element, "configured caps %"GST_PTR_FORMAT, caps);
if (![session isRunning])
[session startRunning];
/* Unlock device configuration only after session is started so the session
* won't reset the capture formats */
[device unlockForConfiguration];
});
return success;
}
- (BOOL)start
{
bufQueueLock = [[NSConditionLock alloc] initWithCondition:NO_BUFFERS];
bufQueue = [[NSMutableArray alloc] initWithCapacity:BUFFER_QUEUE_SIZE];
stopRequest = NO;
offset = 0;
latency = GST_CLOCK_TIME_NONE;
lastSampling = GST_CLOCK_TIME_NONE;
count = 0;
fps = -1;
return YES;
}
- (BOOL)stop
{
dispatch_sync (mainQueue, ^{ [session stopRunning]; });
dispatch_sync (workerQueue, ^{});
[bufQueueLock release];
bufQueueLock = nil;
[bufQueue release];
bufQueue = nil;
if (textureCache)
gst_video_texture_cache_free (textureCache);
textureCache = NULL;
if (ctxh)
gst_gl_context_helper_free (ctxh);
ctxh = NULL;
return YES;
}
- (BOOL)query:(GstQuery *)query
{
BOOL result = NO;
if (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY) {
if (device != nil && caps != NULL) {
GstClockTime min_latency, max_latency;
min_latency = max_latency = latency;
result = YES;
GST_DEBUG_OBJECT (element, "reporting latency of min %" GST_TIME_FORMAT
" max %" GST_TIME_FORMAT,
GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
gst_query_set_latency (query, TRUE, min_latency, max_latency);
}
} else {
result = GST_BASE_SRC_CLASS (parent_class)->query (baseSrc, query);
}
return result;
}
- (BOOL)unlock
{
[bufQueueLock lock];
stopRequest = YES;
[bufQueueLock unlockWithCondition:HAS_BUFFER_OR_STOP_REQUEST];
return YES;
}
- (BOOL)unlockStop
{
[bufQueueLock lock];
stopRequest = NO;
[bufQueueLock unlockWithCondition:([bufQueue count] == 0) ? NO_BUFFERS : HAS_BUFFER_OR_STOP_REQUEST];
return YES;
}
- (GstStateChangeReturn)changeState:(GstStateChange)transition
{
GstStateChangeReturn ret;
if (transition == GST_STATE_CHANGE_NULL_TO_READY) {
if (![self openDevice])
return GST_STATE_CHANGE_FAILURE;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (transition == GST_STATE_CHANGE_READY_TO_NULL)
[self closeDevice];
return ret;
}
- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
fromConnection:(AVCaptureConnection *)aConnection
{
GstClockTime timestamp, duration;
[bufQueueLock lock];
if (stopRequest) {
[bufQueueLock unlock];
return;
}
[self getSampleBuffer:sampleBuffer timestamp:&timestamp duration:&duration];
if (timestamp == GST_CLOCK_TIME_NONE) {
[bufQueueLock unlockWithCondition:([bufQueue count] == 0) ? NO_BUFFERS : HAS_BUFFER_OR_STOP_REQUEST];
return;
}
if ([bufQueue count] == BUFFER_QUEUE_SIZE)
[bufQueue removeLastObject];
[bufQueue insertObject:@{@"sbuf": (id)sampleBuffer,
@"timestamp": @(timestamp),
@"duration": @(duration)}
atIndex:0];
[bufQueueLock unlockWithCondition:HAS_BUFFER_OR_STOP_REQUEST];
}
- (GstFlowReturn)create:(GstBuffer **)buf
{
CMSampleBufferRef sbuf;
CVImageBufferRef image_buf;
CVPixelBufferRef pixel_buf;
size_t cur_width, cur_height;
GstClockTime timestamp, duration;
[bufQueueLock lockWhenCondition:HAS_BUFFER_OR_STOP_REQUEST];
if (stopRequest) {
[bufQueueLock unlock];
return GST_FLOW_FLUSHING;
}
NSDictionary *dic = (NSDictionary *) [bufQueue lastObject];
sbuf = (CMSampleBufferRef) dic[@"sbuf"];
timestamp = (GstClockTime) [dic[@"timestamp"] longLongValue];
duration = (GstClockTime) [dic[@"duration"] longLongValue];
CFRetain (sbuf);
[bufQueue removeLastObject];
[bufQueueLock unlockWithCondition:
([bufQueue count] == 0) ? NO_BUFFERS : HAS_BUFFER_OR_STOP_REQUEST];
/* Check output frame size dimensions */
image_buf = CMSampleBufferGetImageBuffer (sbuf);
if (image_buf) {
pixel_buf = (CVPixelBufferRef) image_buf;
cur_width = CVPixelBufferGetWidth (pixel_buf);
cur_height = CVPixelBufferGetHeight (pixel_buf);
if (width != cur_width || height != cur_height) {
/* Set new caps according to current frame dimensions */
GST_WARNING ("Output frame size has changed %dx%d -> %dx%d, updating caps",
width, height, (int)cur_width, (int)cur_height);
width = cur_width;
height = cur_height;
gst_caps_set_simple (caps,
"width", G_TYPE_INT, width,
"height", G_TYPE_INT, height,
NULL);
gst_pad_push_event (GST_BASE_SINK_PAD (baseSrc), gst_event_new_caps (caps));
}
}
*buf = gst_core_media_buffer_new (sbuf, useVideoMeta);
if (*buf == NULL) {
CFRelease (sbuf);
return GST_FLOW_ERROR;
}
CFRelease (sbuf);
if (textureCache != NULL) {
*buf = gst_video_texture_cache_get_gl_buffer (textureCache, *buf);
if (*buf == NULL)
return GST_FLOW_ERROR;
}
GST_BUFFER_OFFSET (*buf) = offset++;
GST_BUFFER_OFFSET_END (*buf) = GST_BUFFER_OFFSET (*buf) + 1;
GST_BUFFER_TIMESTAMP (*buf) = timestamp;
GST_BUFFER_DURATION (*buf) = duration;
if (doStats)
[self updateStatistics];
return GST_FLOW_OK;
}
- (GstCaps *)fixate:(GstCaps *)new_caps
{
GstStructure *structure;
new_caps = gst_caps_make_writable (new_caps);
new_caps = gst_caps_truncate (new_caps);
structure = gst_caps_get_structure (new_caps, 0);
/* crank up to 11. This is what the presets do, but we don't use the presets
* in ios >= 7.0 */
gst_structure_fixate_field_nearest_int (structure, "height", G_MAXINT);
gst_structure_fixate_field_nearest_fraction (structure, "framerate", G_MAXINT, 1);
return gst_caps_fixate (new_caps);
}
- (BOOL)decideAllocation:(GstQuery *)query
{
GstCaps *alloc_caps;
GstCapsFeatures *features;
gboolean ret;
ret = GST_BASE_SRC_CLASS (parent_class)->decide_allocation (baseSrc, query);
if (!ret)
return ret;
gst_query_parse_allocation (query, &alloc_caps, NULL);
features = gst_caps_get_features (alloc_caps, 0);
if (gst_caps_features_contains (features, GST_CAPS_FEATURE_MEMORY_GL_MEMORY)) {
gst_gl_context_helper_ensure_context (ctxh);
GST_INFO_OBJECT (element, "pushing textures, context %p old context %p",
ctxh->context, textureCache ? textureCache->ctx : NULL);
if (textureCache && textureCache->ctx != ctxh->context) {
gst_video_texture_cache_free (textureCache);
textureCache = NULL;
}
textureCache = gst_video_texture_cache_new (ctxh->context);
gst_video_texture_cache_set_format (textureCache, format, alloc_caps);
}
return TRUE;
}
- (void)setContext:(GstContext *)context
{
GST_INFO_OBJECT (element, "setting context %s",
gst_context_get_context_type (context));
gst_gl_handle_set_context (element, context,
&ctxh->display, &ctxh->other_context);
GST_ELEMENT_CLASS (parent_class)->set_context (element, context);
}
- (void)getSampleBuffer:(CMSampleBufferRef)sbuf
timestamp:(GstClockTime *)outTimestamp
duration:(GstClockTime *)outDuration
{
CMSampleTimingInfo time_info;
GstClockTime timestamp, avf_timestamp, duration, input_clock_now, input_clock_diff, running_time;
CMItemCount num_timings;
GstClock *clock;
CMTime now;
timestamp = GST_CLOCK_TIME_NONE;
duration = GST_CLOCK_TIME_NONE;
if (CMSampleBufferGetOutputSampleTimingInfoArray(sbuf, 1, &time_info, &num_timings) == noErr) {
avf_timestamp = gst_util_uint64_scale (GST_SECOND,
time_info.presentationTimeStamp.value, time_info.presentationTimeStamp.timescale);
if (CMTIME_IS_VALID (time_info.duration) && time_info.duration.timescale != 0)
duration = gst_util_uint64_scale (GST_SECOND,
time_info.duration.value, time_info.duration.timescale);
now = CMClockGetTime(inputClock);
input_clock_now = gst_util_uint64_scale (GST_SECOND,
now.value, now.timescale);
input_clock_diff = input_clock_now - avf_timestamp;
GST_OBJECT_LOCK (element);
clock = GST_ELEMENT_CLOCK (element);
if (clock) {
running_time = gst_clock_get_time (clock) - element->base_time;
/* We use presentationTimeStamp to determine how much time it took
* between capturing and receiving the frame in our delegate
* (e.g. how long it spent in AVF queues), then we subtract that time
* from our running time to get the actual timestamp.
*/
if (running_time >= input_clock_diff)
timestamp = running_time - input_clock_diff;
else
timestamp = running_time;
GST_DEBUG_OBJECT (element, "AVF clock: %"GST_TIME_FORMAT ", AVF PTS: %"GST_TIME_FORMAT
", AVF clock diff: %"GST_TIME_FORMAT
", running time: %"GST_TIME_FORMAT ", out PTS: %"GST_TIME_FORMAT,
GST_TIME_ARGS (input_clock_now), GST_TIME_ARGS (avf_timestamp),
GST_TIME_ARGS (input_clock_diff),
GST_TIME_ARGS (running_time), GST_TIME_ARGS (timestamp));
} else {
/* no clock, can't set timestamps */
timestamp = GST_CLOCK_TIME_NONE;
}
GST_OBJECT_UNLOCK (element);
}
*outTimestamp = timestamp;
*outDuration = duration;
}
- (void)updateStatistics
{
GstClock *clock;
GST_OBJECT_LOCK (element);
clock = GST_ELEMENT_CLOCK (element);
if (clock != NULL)
gst_object_ref (clock);
GST_OBJECT_UNLOCK (element);
if (clock != NULL) {
GstClockTime now = gst_clock_get_time (clock);
gst_object_unref (clock);
count++;
if (GST_CLOCK_TIME_IS_VALID (lastSampling)) {
if (now - lastSampling >= GST_SECOND) {
GST_OBJECT_LOCK (element);
fps = count;
GST_OBJECT_UNLOCK (element);
g_object_notify (G_OBJECT (element), "fps");
lastSampling = now;
count = 0;
}
} else {
lastSampling = now;
}
}
}
@end
/*
* Glue code
*/
enum
{
PROP_0,
PROP_DEVICE_INDEX,
PROP_DO_STATS,
PROP_FPS,
#if !HAVE_IOS
PROP_CAPTURE_SCREEN,
PROP_CAPTURE_SCREEN_CURSOR,
PROP_CAPTURE_SCREEN_MOUSE_CLICKS,
#endif
};
static void gst_avf_video_src_finalize (GObject * obj);
static void gst_avf_video_src_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_avf_video_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static GstStateChangeReturn gst_avf_video_src_change_state (
GstElement * element, GstStateChange transition);
static GstCaps * gst_avf_video_src_get_caps (GstBaseSrc * basesrc,
GstCaps * filter);
static gboolean gst_avf_video_src_set_caps (GstBaseSrc * basesrc,
GstCaps * caps);
static gboolean gst_avf_video_src_start (GstBaseSrc * basesrc);
static gboolean gst_avf_video_src_stop (GstBaseSrc * basesrc);
static gboolean gst_avf_video_src_query (GstBaseSrc * basesrc,
GstQuery * query);
static gboolean gst_avf_video_src_unlock (GstBaseSrc * basesrc);
static gboolean gst_avf_video_src_unlock_stop (GstBaseSrc * basesrc);
static GstFlowReturn gst_avf_video_src_create (GstPushSrc * pushsrc,
GstBuffer ** buf);
static GstCaps * gst_avf_video_src_fixate (GstBaseSrc * bsrc,
GstCaps * caps);
static gboolean gst_avf_video_src_decide_allocation (GstBaseSrc * bsrc,
GstQuery * query);
static void gst_avf_video_src_set_context (GstElement * element,
GstContext * context);
static void
gst_avf_video_src_class_init (GstAVFVideoSrcClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
GstBaseSrcClass *gstbasesrc_class = GST_BASE_SRC_CLASS (klass);
GstPushSrcClass *gstpushsrc_class = GST_PUSH_SRC_CLASS (klass);
gobject_class->finalize = gst_avf_video_src_finalize;
gobject_class->get_property = gst_avf_video_src_get_property;
gobject_class->set_property = gst_avf_video_src_set_property;
gstelement_class->change_state = gst_avf_video_src_change_state;
gstelement_class->set_context = gst_avf_video_src_set_context;
gstbasesrc_class->get_caps = gst_avf_video_src_get_caps;
gstbasesrc_class->set_caps = gst_avf_video_src_set_caps;
gstbasesrc_class->start = gst_avf_video_src_start;
gstbasesrc_class->stop = gst_avf_video_src_stop;
gstbasesrc_class->query = gst_avf_video_src_query;
gstbasesrc_class->unlock = gst_avf_video_src_unlock;
gstbasesrc_class->unlock_stop = gst_avf_video_src_unlock_stop;
gstbasesrc_class->fixate = gst_avf_video_src_fixate;
gstbasesrc_class->decide_allocation = gst_avf_video_src_decide_allocation;
gstpushsrc_class->create = gst_avf_video_src_create;
gst_element_class_set_metadata (gstelement_class,
"Video Source (AVFoundation)", "Source/Video",
"Reads frames from an iOS AVFoundation device",
"Ole André Vadla Ravnås <oleavr@soundrop.com>");
gst_element_class_add_static_pad_template (gstelement_class, &src_template);
g_object_class_install_property (gobject_class, PROP_DEVICE_INDEX,
g_param_spec_int ("device-index", "Device Index",
"The zero-based device index",
-1, G_MAXINT, DEFAULT_DEVICE_INDEX,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_DO_STATS,
g_param_spec_boolean ("do-stats", "Enable statistics",
"Enable logging of statistics", DEFAULT_DO_STATS,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_FPS,
g_param_spec_int ("fps", "Frames per second",
"Last measured framerate, if statistics are enabled",
-1, G_MAXINT, -1, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
#if !HAVE_IOS
g_object_class_install_property (gobject_class, PROP_CAPTURE_SCREEN,
g_param_spec_boolean ("capture-screen", "Enable screen capture",
"Enable screen capture functionality", FALSE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_CAPTURE_SCREEN_CURSOR,
g_param_spec_boolean ("capture-screen-cursor", "Capture screen cursor",
"Enable cursor capture while capturing screen", FALSE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_CAPTURE_SCREEN_MOUSE_CLICKS,
g_param_spec_boolean ("capture-screen-mouse-clicks", "Enable mouse clicks capture",
"Enable mouse clicks capture while capturing screen", FALSE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
#endif
GST_DEBUG_CATEGORY_INIT (gst_avf_video_src_debug, "avfvideosrc",
0, "iOS AVFoundation video source");
}
#define OBJC_CALLOUT_BEGIN() \
NSAutoreleasePool *pool; \
\
pool = [[NSAutoreleasePool alloc] init]
#define OBJC_CALLOUT_END() \
[pool release]
static void
gst_avf_video_src_init (GstAVFVideoSrc * src)
{
OBJC_CALLOUT_BEGIN ();
src->impl = [[GstAVFVideoSrcImpl alloc] initWithSrc:GST_PUSH_SRC (src)];
OBJC_CALLOUT_END ();
}
static void
gst_avf_video_src_finalize (GObject * obj)
{
OBJC_CALLOUT_BEGIN ();
[GST_AVF_VIDEO_SRC_IMPL (obj) release];
OBJC_CALLOUT_END ();
G_OBJECT_CLASS (parent_class)->finalize (obj);
}
static void
gst_avf_video_src_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstAVFVideoSrcImpl *impl = GST_AVF_VIDEO_SRC_IMPL (object);
switch (prop_id) {
#if !HAVE_IOS
case PROP_CAPTURE_SCREEN:
g_value_set_boolean (value, impl.captureScreen);
break;
case PROP_CAPTURE_SCREEN_CURSOR:
g_value_set_boolean (value, impl.captureScreenCursor);
break;
case PROP_CAPTURE_SCREEN_MOUSE_CLICKS:
g_value_set_boolean (value, impl.captureScreenMouseClicks);
break;
#endif
case PROP_DEVICE_INDEX:
g_value_set_int (value, impl.deviceIndex);
break;
case PROP_DO_STATS:
g_value_set_boolean (value, impl.doStats);
break;
case PROP_FPS:
GST_OBJECT_LOCK (object);
g_value_set_int (value, impl.fps);
GST_OBJECT_UNLOCK (object);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_avf_video_src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAVFVideoSrcImpl *impl = GST_AVF_VIDEO_SRC_IMPL (object);
switch (prop_id) {
#if !HAVE_IOS
case PROP_CAPTURE_SCREEN:
impl.captureScreen = g_value_get_boolean (value);
break;
case PROP_CAPTURE_SCREEN_CURSOR:
impl.captureScreenCursor = g_value_get_boolean (value);
break;
case PROP_CAPTURE_SCREEN_MOUSE_CLICKS:
impl.captureScreenMouseClicks = g_value_get_boolean (value);
break;
#endif
case PROP_DEVICE_INDEX:
impl.deviceIndex = g_value_get_int (value);
break;
case PROP_DO_STATS:
impl.doStats = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_avf_video_src_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (element) changeState: transition];
OBJC_CALLOUT_END ();
return ret;
}
static GstCaps *
gst_avf_video_src_get_caps (GstBaseSrc * basesrc, GstCaps * filter)
{
GstCaps *ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) getCaps];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_set_caps (GstBaseSrc * basesrc, GstCaps * caps)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) setCaps:caps];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_start (GstBaseSrc * basesrc)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) start];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_stop (GstBaseSrc * basesrc)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) stop];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_query (GstBaseSrc * basesrc, GstQuery * query)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) query:query];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_unlock (GstBaseSrc * basesrc)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) unlock];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_unlock_stop (GstBaseSrc * basesrc)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (basesrc) unlockStop];
OBJC_CALLOUT_END ();
return ret;
}
static GstFlowReturn
gst_avf_video_src_create (GstPushSrc * pushsrc, GstBuffer ** buf)
{
GstFlowReturn ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (pushsrc) create: buf];
OBJC_CALLOUT_END ();
return ret;
}
static GstCaps *
gst_avf_video_src_fixate (GstBaseSrc * bsrc, GstCaps * caps)
{
GstCaps *ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (bsrc) fixate:caps];
OBJC_CALLOUT_END ();
return ret;
}
static gboolean
gst_avf_video_src_decide_allocation (GstBaseSrc * bsrc,
GstQuery * query)
{
gboolean ret;
OBJC_CALLOUT_BEGIN ();
ret = [GST_AVF_VIDEO_SRC_IMPL (bsrc) decideAllocation:query];
OBJC_CALLOUT_END ();
return ret;
}
static void
gst_avf_video_src_set_context (GstElement * element, GstContext * context)
{
OBJC_CALLOUT_BEGIN ();
[GST_AVF_VIDEO_SRC_IMPL (element) setContext:context];
OBJC_CALLOUT_END ();
}