On 30.03.2014 21:17, Thilo Borgmann wrote:

...

From a44489698c7237988817a63e55058e0d49b120dc Mon Sep 17 00:00:00 2001 From: Thilo Borgmann<thilo.borgmann@mail.de> Date: Sun, 30 Mar 2014 21:13:04 +0200 Subject: [PATCH 1/2] lavd/qtkit: Support choosing the input device by index or by name.

--- doc/indevs.texi | 8 +++++++- libavdevice/qtkit.m | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 59 insertions(+), 3 deletions(-)

diff --git a/doc/indevs.texi b/doc/indevs.texi index e1ff231..b54df72 100644 --- a/doc/indevs.texi +++ b/doc/indevs.texi @@ -535,12 +535,18 @@ ffmpeg -f pulse -i default /tmp/pulse.wav

QTKit input device.

-The filename passed as input is unused. The default device will be chosen. +The filename passed as input is parsed to contain either a device name or index. +The default device will be chosen if an empty string is given. +The available devices can be enumerated by using -list_devices.

@example ffmpeg -f isight -i "" out.mpg @end example

+@example +ffmpeg -f qtkit -list_devices true -i "" +@end example + @section sndio

sndio input device. diff --git a/libavdevice/qtkit.m b/libavdevice/qtkit.m index 038ce02..edcc518 100644 --- a/libavdevice/qtkit.m +++ b/libavdevice/qtkit.m @@ -53,6 +53,9 @@ typedef struct pthread_cond_t frame_wait_cond; id qt_delegate;

+ int list_devices; + int video_device_index; + QTCaptureSession* capture_session; QTCaptureDecompressedVideoOutput* video_output; CVImageBufferRef current_frame; @@ -145,8 +148,51 @@ static int qtkit_read_header(AVFormatContext *s) pthread_mutex_init(&ctx->frame_lock, NULL); pthread_cond_init(&ctx->frame_wait_cond, NULL);

- // Find default capture device - QTCaptureDevice *video_device = [QTCaptureDevice defaultInputDeviceWithMediaType:QTMediaTypeMuxed]; + // List devices if requested + if (ctx->list_devices) { + av_log(ctx, AV_LOG_INFO, "QTKit video devices:\n"); + NSArray *devices = [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo]; + for (QTCaptureDevice *device in devices) { + char *name = [[device localizedDisplayName] UTF8String]; + int index = [devices indexOfObject:device]; + av_log(ctx, AV_LOG_INFO, "[%d] %s\n", index, name); + } + goto fail; + } + + // Find capture device + QTCaptureDevice *video_device = nil; + + // check for device index given in filename + if (ctx->video_device_index == -1) { + sscanf(s->filename, "%d", &ctx->video_device_index); + }

I'm not sure it is required. It can possibly lead to scan a random number that is a part of device name.

+ if (ctx->video_device_index != -1) { + NSArray *devices = [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo]; + + if (ctx->video_device_index >= [devices count]) { + av_log(ctx, AV_LOG_ERROR, "Invalid device index\n"); + goto fail; + } + + video_device = [devices objectAtIndex:ctx->video_device_index]; + } else if (strncmp(s->filename, "", 1)) {

Many devices uses string "default" for this reason, not empty string. Be free to ignore this, but this would make it more consistent with other devices.

+ NSArray *devices = [QTCaptureDevice inputDevicesWithMediaType:QTMediaTypeVideo]; + + for (QTCaptureDevice *device in devices) { + if (!strncmp(s->filename, [[device localizedDisplayName] UTF8String], strlen(s->filename))) { + video_device = device; + break; + } + } + if (!video_device) { + av_log(ctx, AV_LOG_ERROR, "Video device not found\n"); + goto fail; + } + } else { + video_device = [QTCaptureDevice defaultInputDeviceWithMediaType:QTMediaTypeMuxed]; + }

BOOL success = [video_device open:nil];

@@ -284,6 +330,10 @@ static int qtkit_close(AVFormatContext *s)

static const AVOption options[] = { { "frame_rate", "set frame rate", offsetof(CaptureContext, frame_rate), AV_OPT_TYPE_FLOAT, { .dbl = 30.0 }, 0.1, 30.0, AV_OPT_TYPE_VIDEO_RATE, NULL }, + { "list_devices", "list available devices", offsetof(CaptureContext, list_devices), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM, "list_devices" }, + { "true", "", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "list_devices" }, + { "false", "", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "list_devices" }, + { "video_device_index", "select video device by index for devices with same name (starts at 0)", offsetof(CaptureContext, video_device_index), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM }, { NULL }, };

You may also consider implementing .get_device_list callback to obtain device list programmatically (as another patch).