---
doc/indevs.texi | 3 +-
libavdevice/v4l2.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 54 insertions(+), 7 deletions(-)
diff --git a/doc/indevs.texi b/doc/indevs.texi
index 4405a5b..cdffeaa 100644
--- a/doc/indevs.texi
+++ b/doc/indevs.texi
@@ -267,7 +267,8 @@ the device.
Video4Linux and Video4Linux2 devices only support a limited set of
@var{width}x@var{height} sizes and framerates. You can check which are
supported for example with the command @file{dov4l} for Video4Linux
-devices and the command @file{v4l-info} for Video4Linux2 devices.
+devices and passing @option{list} to @command{-pixel_format} for
+Video4Linux2 devices.
If the size for the device is set to 0x0, the input device will
try to autodetect the size to use.
diff --git a/libavdevice/v4l2.c b/libavdevice/v4l2.c
index 9e8c5e4..6b73005 100644
--- a/libavdevice/v4l2.c
+++ b/libavdevice/v4l2.c
@@ -101,6 +101,40 @@ static struct fmt_map fmt_conversion_table[] = {
{ PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
};
+static void list_formats(AVFormatContext *ctx, int level, int fd)
+{
+ struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
+ struct v4l2_frmsizeenum vfse = { 0 };
+
+ while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
+ av_log(ctx, level,
+ "%c%c%c%c/%04x %s flags %s%s :",
+ vfd.pixelformat & 0xFF,
+ (vfd.pixelformat >> 8) & 0xFF,
+ (vfd.pixelformat >> 16) & 0xFF,
+ (vfd.pixelformat >> 24) & 0xFF,
+ vfd.pixelformat,
+ vfd.description,
+ vfd.flags & V4L2_FMT_FLAG_EMULATED ? "e" : " ",
+ vfd.flags & V4L2_FMT_FLAG_COMPRESSED ? "c": " ");
+
+ vfse.pixel_format = vfd.pixelformat;
+
+ while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
+ av_log(ctx, level,
+ " %ux%u",
+ vfse.discrete.width, vfse.discrete.height);
+ vfse.index++;
+ }
+
+ vfse.index = 0;
+ vfd.index++;
+
+ av_log(ctx, level, "\n");
+ }
+
+};
+
static int device_open(AVFormatContext *ctx)
{
struct v4l2_capability cap;
@@ -626,12 +660,24 @@ static int v4l2_read_header(AVFormatContext *s1,
AVFormatParameters *ap)
s->video_size);
goto out;
}
- if (s->pixel_format &&
- (pix_fmt = av_get_pix_fmt(s->pixel_format)) == PIX_FMT_NONE) {
- av_log(s1, AV_LOG_ERROR, "No such pixel format: %s.\n",
- s->pixel_format);
- res = AVERROR(EINVAL);
- goto out;
+
+ if (s->pixel_format) {
+
+ if (!strcmp(s->pixel_format, "list")) {
+ list_formats(s1, AV_LOG_INFO, s->fd);
+ res = AVERROR_EXIT;
+ goto out;
+ }
+
+ pix_fmt = av_get_pix_fmt(s->pixel_format);
+
+ if (pix_fmt == PIX_FMT_NONE) {
+ av_log(s1, AV_LOG_ERROR, "No such pixel format: %s.\n",
+ s->pixel_format);
+
+ res = AVERROR(EINVAL);
+ goto out;
+ }
}
if (!s->width && !s->height) {
--
1.7.8.rc1
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