[FFmpeg-devel] [PATCH 1/1] libavdevice/v4l2enc: support additional v4l2 output formats

[James Hilliard]

The purpose of this patch is to fix a bug where ffmpeg would only
output rawvideo to a v4l2loopback device even though v4l2loopback
accepts other formats such as mjpeg.

On Wed, Jan 23, 2019 at 7:55 PM <james.hilliard1 at gmail.com> wrote:
>
> From: James Hilliard <james.hilliard1 at gmail.com>
>
> Signed-off-by: James Hilliard <james.hilliard1 at gmail.com>
> ---
>  libavdevice/v4l2enc.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/libavdevice/v4l2enc.c b/libavdevice/v4l2enc.c
> index faf6e07..f778208 100644
> --- a/libavdevice/v4l2enc.c
> +++ b/libavdevice/v4l2enc.c
> @@ -47,8 +47,7 @@ static av_cold int write_header(AVFormatContext *s1)
>      }
>
>      if (s1->nb_streams != 1 ||
> -        s1->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO ||
> -        s1->streams[0]->codecpar->codec_id   != AV_CODEC_ID_RAWVIDEO) {
> +        s1->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO) {
>          av_log(s1, AV_LOG_ERROR,
>                 "V4L2 output device supports only a single raw video stream\n");
>          return AVERROR(EINVAL);
> @@ -56,7 +55,7 @@ static av_cold int write_header(AVFormatContext *s1)
>
>      par = s1->streams[0]->codecpar;
>
> -    v4l2_pixfmt = ff_fmt_ff2v4l(par->format, AV_CODEC_ID_RAWVIDEO);
> +    v4l2_pixfmt = ff_fmt_ff2v4l(AV_PIX_FMT_NONE, s1->streams[0]->codecpar->codec_id);
>      if (!v4l2_pixfmt) { // XXX: try to force them one by one?
>          av_log(s1, AV_LOG_ERROR, "Unknown V4L2 pixel format equivalent for %s\n",
>                 av_get_pix_fmt_name(par->format));
> --
> 2.7.4
>