[FFmpeg-devel] [PATCH 1/4] libavdevice/avfoundation: add framerate and video size options
matthieu.bouron at gmail.com
matthieu.bouron at gmail.com
Fri Mar 13 20:16:52 CET 2015
From: Matthieu Bouron <matthieu.bouron at gmail.com>
Support framerate ands video size options on AVCaptureDevices for
OSX >= 10.7 and iOS >= 7.0.
For screen captures, only the framerate option is taken into account.
---
libavdevice/avfoundation.m | 103 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 103 insertions(+)
diff --git a/libavdevice/avfoundation.m b/libavdevice/avfoundation.m
index e00cc3b..41fe9c3 100644
--- a/libavdevice/avfoundation.m
+++ b/libavdevice/avfoundation.m
@@ -33,6 +33,7 @@
#include "libavutil/avstring.h"
#include "libavformat/internal.h"
#include "libavutil/internal.h"
+#include "libavutil/parseutils.h"
#include "libavutil/time.h"
#include "avdevice.h"
@@ -90,6 +91,9 @@ typedef struct
id avf_delegate;
id avf_audio_delegate;
+ AVRational framerate;
+ int width, height;
+
int list_devices;
int video_device_index;
int video_stream_index;
@@ -263,9 +267,76 @@ static void parse_device_name(AVFormatContext *s)
}
}
+/*
+ * Configure the video device using a run-time approach to access properties
+ * since formats, activeFormat are available since iOS >= 7.0 or OSX >= 10.7
+ * and activeVideoMaxFrameDuration is available since i0S >= 7.0 and OSX >= 10.9
+ *
+ * The NSUndefinedKeyException must be handled by the caller of this function.
+ *
+ */
+static int configure_video_device(AVFormatContext *s, AVCaptureDevice *video_device)
+{
+ AVFContext *ctx = (AVFContext*)s->priv_data;
+
+ double framerate = av_q2d(ctx->framerate);
+ NSObject *selected_format = nil, *selected_range = nil;
+
+ for (NSObject *format in [video_device valueForKey:@"formats"]) {
+ CMFormatDescriptionRef formatDescription;
+ CMVideoDimensions dimensions;
+
+ formatDescription = (CMFormatDescriptionRef) [format performSelector:@selector(formatDescription)];
+ dimensions = CMVideoFormatDescriptionGetDimensions(formatDescription);
+
+ if ((ctx->width == 0 && ctx->height == 0) ||
+ (dimensions.width == ctx->width && dimensions.height == ctx->height)) {
+
+ selected_format = format;
+
+ for (NSObject *range in [format valueForKey:@"videoSupportedFrameRateRanges"]) {
+ double max_framerate;
+
+ [[range valueForKey:@"maxFrameRate"] getValue:&max_framerate];
+ if (framerate == 0.0 || abs (framerate - max_framerate) < 0.00001) {
+
+ selected_range = range;
+ break;
+ }
+ }
+ }
+ }
+
+ if (!selected_format) {
+ av_log(s, AV_LOG_ERROR, "Selected video size (%dx%d) is not supported by the device\n",
+ ctx->width, ctx->height);
+ return AVERROR(EINVAL);
+ }
+
+ if (!selected_range) {
+ av_log(s, AV_LOG_ERROR, "Selected framerate (%f) is not supported by the device\n",
+ framerate);
+ return AVERROR(EINVAL);
+ }
+
+ if ([video_device lockForConfiguration:NULL] == YES) {
+ NSValue *min_frame_duration = [selected_range valueForKey:@"minFrameDuration"];
+
+ [video_device setValue:selected_format forKey:@"activeFormat"];
+ [video_device setValue:min_frame_duration forKey:@"activeVideoMinFrameDuration"];
+ [video_device setValue:min_frame_duration forKey:@"activeVideoMaxFrameDuration"];
+ } else {
+ av_log(s, AV_LOG_ERROR, "Could not lock device for configuration");
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+
static int add_video_device(AVFormatContext *s, AVCaptureDevice *video_device)
{
AVFContext *ctx = (AVFContext*)s->priv_data;
+ int ret;
NSError *error = nil;
AVCaptureInput* capture_input = nil;
struct AVFPixelFormatSpec pxl_fmt_spec;
@@ -300,6 +371,18 @@ static int add_video_device(AVFormatContext *s, AVCaptureDevice *video_device)
return 1;
}
+ // Configure device framerate and video size
+ @try {
+ if ((ret = configure_video_device(s, video_device)) < 0) {
+ return ret;
+ }
+ } @catch (NSException *exception) {
+ if (![[exception name] isEqualToString:NSUndefinedKeyException]) {
+ av_log (s, AV_LOG_ERROR, "An error occured: %s", [exception.reason UTF8String]);
+ return AVERROR_EXTERNAL;
+ }
+ }
+
// select pixel format
pxl_fmt_spec.ff_id = AV_PIX_FMT_NONE;
@@ -549,6 +632,7 @@ static int get_audio_config(AVFormatContext *s)
static int avf_read_header(AVFormatContext *s)
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
+ int capture_screen = 0;
uint32_t num_screens = 0;
AVFContext *ctx = (AVFContext*)s->priv_data;
AVCaptureDevice *video_device = nil;
@@ -616,7 +700,13 @@ static int avf_read_header(AVFormatContext *s)
CGDirectDisplayID screens[num_screens];
CGGetActiveDisplayList(num_screens, screens, &num_screens);
AVCaptureScreenInput* capture_screen_input = [[[AVCaptureScreenInput alloc] initWithDisplayID:screens[ctx->video_device_index - ctx->num_video_devices]] autorelease];
+
+ if (ctx->framerate.num > 0) {
+ capture_screen_input.minFrameDuration = CMTimeMake(ctx->framerate.den, ctx->framerate.num);
+ }
+
video_device = (AVCaptureDevice*) capture_screen_input;
+ capture_screen = 1;
#endif
} else {
av_log(ctx, AV_LOG_ERROR, "Invalid device index\n");
@@ -645,6 +735,11 @@ static int avf_read_header(AVFormatContext *s)
AVCaptureScreenInput* capture_screen_input = [[[AVCaptureScreenInput alloc] initWithDisplayID:screens[idx]] autorelease];
video_device = (AVCaptureDevice*) capture_screen_input;
ctx->video_device_index = ctx->num_video_devices + idx;
+ capture_screen = 1;
+
+ if (ctx->framerate.num > 0) {
+ capture_screen_input.minFrameDuration = CMTimeMake(ctx->framerate.den, ctx->framerate.num);
+ }
}
}
#endif
@@ -715,6 +810,12 @@ static int avf_read_header(AVFormatContext *s)
[ctx->capture_session startRunning];
+ /* Unlock device configuration only after the session is started so it
+ * does not reset the capture formats */
+ if (!capture_screen) {
+ [video_device unlockForConfiguration];
+ }
+
if (video_device && get_video_config(s)) {
goto fail;
}
@@ -853,6 +954,8 @@ static const AVOption options[] = {
{ "video_device_index", "select video device by index for devices with same name (starts at 0)", offsetof(AVFContext, video_device_index), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
{ "audio_device_index", "select audio device by index for devices with same name (starts at 0)", offsetof(AVFContext, audio_device_index), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
{ "pixel_format", "set pixel format", offsetof(AVFContext, pixel_format), AV_OPT_TYPE_PIXEL_FMT, {.i64 = AV_PIX_FMT_YUV420P}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM},
+ { "framerate", "set frame rate", offsetof(AVFContext, framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "ntsc"}, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
+ { "size", "set video size", offsetof(AVFContext, width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
{ NULL },
};
--
2.3.2
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