On Fri, Oct 18, 2019 at 4:00 PM Sakari Ailus <[email protected]> wrote:
>
> HI Adam,
>
> On Fri, Oct 18, 2019 at 02:38:57PM -0500, Adam Ford wrote:
> > I have a DM3730 with a parallel mt9p031 sensor attached. I am trying
> > to troubleshoot some issues with streaming video with G-streamer, but
> > I I think the issue is in how the ISP driver reports the video info.
> >
> > I have the pipeline to grab from the resizer:
> >
> > media-ctl -v -V '"mt9p031 1-0048":0 [SGRBG8 1280x720
> > (664,541)/1280x720], "OMAP3 ISP CCDC":2 [SGRBG8 1280x720], "OMAP3 ISP
> > preview":1 [UYVY 1280x720], "OMAP3 ISP resizer":1 [UYVY 480x272]'
> >
> > This make /dev/video6 the output of the resizer and shows the format
> > and resolution of the output of the resizer as:
> >
> > Setting up format UYVY8_1X16 480x272 on pad OMAP3 ISP resizer/1
> > Format set: UYVY8_1X16 480x272
> >
> > I used 480x272 because it's the resolution of my LCD, and I was hoping
> > the resizer would be able to scale this so the ARM would not need to
> > do the work, and it appears to not have any issues with this
> > resolution.
> >
> > However, if I query the video format, I don't get UYVY:
> >
> > # v4l2-ctl -d6 --list-formats-ext
> > ioctl: VIDIOC_ENUM_FMT
> > Type: Video Capture
> >
> > [0]: 'RGB3' (RGB3, emulated)
> > [1]: 'BGR3' (BGR3, emulated)
> > [2]: 'YU12' (YU12, emulated)
> > [3]: 'YV12' (YV12, emulated)
> >
> > This becomes an issue when I attempt to stream video from my camera to
> > anything, include fake sink:
> >
> > gst-launch-1.0 -v v4l2src device=/dev/video6 ! fakesink
> > Tried to capture in RGB3, but device returned format UYVY
> >
> > So for some reason, when queried, it reports different values than
> > UYVY, but when attempting to set the video capture to the listed
> > formats, it returns an error.
> >
> > gst-launch-1.0 -v v4l2src device=/dev/video6 ! video/x-raw,
> > format=UYVY ! fakesink
>
> I don't have any experience on v4l2src recently but I can comment on the
> omap3isp driver.
>
> In general, the format the omap3isp may produce on a given video node
> depends on the format of data which the block associated with the video
> node is fed with.
>
> For instance, in case of the raw Bayer formats, the pixel order does not
> change, and thus the pixel order remains all the way from the sensor to the
> video node.
>From what I can tell, it looks like the output of the resizer is only
capable of two formats,
from ispresizer.c:
/* resizer pixel formats */
static const unsigned int resizer_formats[] = {
MEDIA_BUS_FMT_UYVY8_1X16,
MEDIA_BUS_FMT_YUYV8_1X16,
};
Also:
* resizer_try_format - Handle try format by pad subdev method
* @res : ISP resizer device
* @cfg: V4L2 subdev pad configuration
* @pad : pad num
* @fmt : pointer to v4l2 format structure
* @which : wanted subdev format
switch (pad) {
case RESZ_PAD_SINK:
if (fmt->code != MEDIA_BUS_FMT_YUYV8_1X16 &&
fmt->code != MEDIA_BUS_FMT_UYVY8_1X16)
fmt->code = MEDIA_BUS_FMT_YUYV8_1X16;
So it looks to me like if we're trying to do anything other than
either of those,we set it to MEDIA_BUS_FMT_YUYV8_1X16
Am I missing something?
>
> This also means that there is no way to provide an enumeration of supported
> formats without knowing the media bus format. There have been proposals to
> support ENUM_FMT in such cases by providing the source media bus format,
> but those proposals haven't materialised into patches.
>
> So for now, the format needs to be simply set using S_FMT.
>
> >
> > Setting pipeline to PAUSED ...
> > Pipeline is live and does not need PREROLL ...
> > Setting pipeline to PLAYING ...
> > New clock: GstSystemClock
> > ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
> > Internal data stream error.
> > Additional debug info:
> > gstbasesrc.c(3055): gst_base_src_loop ():
> > /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
> > streaming stopped, reason not-negotiated (-4)
> >
> > This leads me to believe that v4l2 is trying to set the format to
> > something it does not think it is able to negotiate, and it's being
> > rejected.
> >
> > I can even explicitly set the output video format to UYVY with:
> >
> > v4l2-ctl -d /dev/video6
> > --set-fmt-video=width=480,height=272,pixelformat=UYVY --verbose
> >
> > VIDIOC_QUERYCAP: ok
> > VIDIOC_G_FMT: ok
> > VIDIOC_S_FMT: ok
> > Format Video Capture:
> > Width/Height : 480/272
> > Pixel Format : 'UYVY'
> > Field : None
> > Bytes per Line : 960
> > Size Image : 261120
> > Colorspace : JPEG
> > Transfer Function : Default (maps to sRGB)
> > YCbCr/HSV Encoding: Default (maps to ITU-R 601)
> > Quantization : Default (maps to Full Range)
> > Flags :
> > #
> >
> > This shows me the UYVY format, but upon a follow-up query, it does not
> > appear to retain the pixel format of UYVY.
> >
> > v4l2-ctl -d /dev/video6 --list-formats-ext
> > ioctl: VIDIOC_ENUM_FMT
> > Type: Video Capture
> >
> > [0]: 'RGB3' (RGB3, emulated)
> > [1]: 'BGR3' (BGR3, emulated)
> > [2]: 'YU12' (YU12, emulated)
> > [3]: 'YV12' (YV12, emulated)
> > #
> >
> > If I use ffmpeg to stream video, I the video codec there recognizes it
> > as uyvy and I can convert it to RGB to display on my LCD, but it has
> > limited framerate, and it seems to me like this should be do-able in
> > G-Streamer with v4l2src.
> >
> > # ffmpeg -an -re -i /dev/video6 -f v4l2 -vcodec rawvideo -pix_fmt bgra
> > -f fbdev /dev/fb0
> >
> > Input #0, video4linux2,v4l2, from '/dev/video6':
> > Duration: N/A, start: 908.826490, bitrate: N/A
> > Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422,
> > 480x272, 17.42 tbr, 1000k tbn, 1000k tbc
> > Stream mapping:
> > Stream #0:0 -> #0:0 (rawvideo (native) -> rawvideo (native))
> > Press [q] to stop, [?] for help
> > Output #0, fbdev, to '/dev/fb0':
> > Metadata:
> > encoder : Lavf57.83.100
> > Stream #0:0: Video: rawvideo (BGRA / 0x41524742), bgra, 480x272,
> > q=2-31, 72765 kb/s, 17.42 fps, 17.42 tbn, 17.42 tbc
> > Metadata:
> > encoder : Lavc57.107.100 rawvideo
> >
> >
> > This shows me the information is available in some ways from v4l2, but
> > I wonder if there is a missing IOCTL for VIDIOC_ENUM_FMT for the isp
> > driver somewhere. Shouldn't VIDIOC_ENUM_FMT return UYVY?
> >
> > I noticed vpbe_display.c has a function that appears to correspond to
> > this. There is a patch at [1] for an older kernel. Is this something
> > worth pursuing?
> >
> > [1] -
> > https://stackoverflow.com/questions/20693155/gstreamer-failed-to-enumerate-video-formats-and-inappropriate-ioctl-for-device
>
> --
> Kind regards,
>
> Sakari Ailus
