[FFmpeg-cvslog] v4l2: list available formats
Luca Barbato
git at videolan.org
Thu Jan 5 02:18:55 CET 2012
ffmpeg | branch: master | Luca Barbato <lu_zero at gentoo.org> | Tue Dec 27 06:31:41 2011 +0100| [a6a4793d045cda277f0ec4579d206b36e3cf90b6] | committer: Luca Barbato
v4l2: list available formats
Make use of the experimental framesize enumeration ioctl if available.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=a6a4793d045cda277f0ec4579d206b36e3cf90b6
---
configure | 3 ++
doc/indevs.texi | 2 +-
libavdevice/v4l2.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++----
3 files changed, 96 insertions(+), 8 deletions(-)
diff --git a/configure b/configure
index 481f0ea..9bf65d2 100755
--- a/configure
+++ b/configure
@@ -1135,6 +1135,7 @@ HAVE_LIST="
struct_sockaddr_in6
struct_sockaddr_sa_len
struct_sockaddr_storage
+ struct_v4l2_frmivalenum_discrete
symver
symver_asm_label
symver_gnu_asm
@@ -2993,6 +2994,8 @@ texi2html -version > /dev/null 2>&1 && enable texi2html || disable texi2html
check_header linux/fb.h
check_header linux/videodev.h
check_header linux/videodev2.h
+check_struct linux/videodev2.h "struct v4l2_frmivalenum" discrete
+
check_header sys/videoio.h
check_func_headers "windows.h vfw.h" capCreateCaptureWindow "$vfwcap_indev_extralibs"
diff --git a/doc/indevs.texi b/doc/indevs.texi
index 4405a5b..e1b4ddd 100644
--- a/doc/indevs.texi
+++ b/doc/indevs.texi
@@ -267,7 +267,7 @@ the device.
Video4Linux and Video4Linux2 devices only support a limited set of
@var{width}x at 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 using @command{-list_formats all} 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 cde2f9f..2895a01 100644
--- a/libavdevice/v4l2.c
+++ b/libavdevice/v4l2.c
@@ -51,6 +51,10 @@
static const int desired_video_buffers = 256;
+#define V4L_ALLFORMATS 3
+#define V4L_RAWFORMATS 1
+#define V4L_COMPFORMATS 2
+
struct video_data {
AVClass *class;
int fd;
@@ -65,8 +69,10 @@ struct video_data {
unsigned int *buf_len;
char *standard;
int channel;
- char *video_size; /**< String describing video size, set by a private option. */
+ char *video_size; /**< String describing video size,
+ set by a private option. */
char *pixel_format; /**< Set by a private option. */
+ int list_format; /**< Set by a private option. */
char *framerate; /**< Set by a private option. */
};
@@ -258,6 +264,69 @@ static enum CodecID fmt_v4l2codec(uint32_t v4l2_fmt)
return CODEC_ID_NONE;
}
+#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
+static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat)
+{
+ struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
+
+ while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
+ switch (vfse.type) {
+ case V4L2_FRMSIZE_TYPE_DISCRETE:
+ av_log(ctx, AV_LOG_INFO, " %ux%u",
+ vfse.discrete.width, vfse.discrete.height);
+ break;
+ case V4L2_FRMSIZE_TYPE_CONTINUOUS:
+ case V4L2_FRMSIZE_TYPE_STEPWISE:
+ av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
+ vfse.stepwise.min_width,
+ vfse.stepwise.max_width,
+ vfse.stepwise.step_width,
+ vfse.stepwise.min_height,
+ vfse.stepwise.max_height,
+ vfse.stepwise.step_height);
+ }
+ vfse.index++;
+ }
+}
+#endif
+
+static void list_formats(AVFormatContext *ctx, int fd, int type)
+{
+ struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
+
+ while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
+ enum CodecID codec_id = fmt_v4l2codec(vfd.pixelformat);
+ enum PixelFormat pix_fmt = fmt_v4l2ff(vfd.pixelformat, codec_id);
+
+ vfd.index++;
+
+ if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
+ type & V4L_RAWFORMATS) {
+ const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
+ av_log(ctx, AV_LOG_INFO, "R : %9s : %20s :",
+ fmt_name ? fmt_name : "Unsupported",
+ vfd.description);
+ } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
+ type & V4L_COMPFORMATS) {
+ AVCodec *codec = avcodec_find_encoder(codec_id);
+ av_log(ctx, AV_LOG_INFO, "C : %9s : %20s :",
+ codec ? codec->name : "Unsupported",
+ vfd.description);
+ } else {
+ continue;
+ }
+
+ if (vfd.flags & V4L2_FMT_FLAG_EMULATED) {
+ av_log(ctx, AV_LOG_WARNING, "%s", "Emulated");
+ continue;
+ }
+#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
+ list_framesizes(ctx, fd, vfd.pixelformat);
+#endif
+ av_log(ctx, AV_LOG_INFO, "\n");
+ }
+}
+
static int mmap_init(AVFormatContext *ctx)
{
struct video_data *s = ctx->priv_data;
@@ -621,6 +690,12 @@ static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
goto out;
}
+ if (s->list_format) {
+ list_formats(s1, s->fd, s->list_format);
+ res = AVERROR_EXIT;
+ goto out;
+ }
+
avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
if (s->video_size &&
@@ -629,12 +704,18 @@ 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) {
+
+ 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) {
@@ -737,6 +818,10 @@ static const AVOption options[] = {
{ "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
{ "pixel_format", "", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
{ "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
+ { "list_formats", "List available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC, "list_formats" },
+ { "all", "Show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
+ { "raw", "Show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
+ { "compressed", "Show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
{ NULL },
};
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