I have usb camera that produces sequence of jpeg images that can not be decoded by omxmjpegdec correctly.

# ls -l
total 104
-rw-r--r-- 1 root root  7313 Jan  3 18:43 image-00.jpeg
-rw-r--r-- 1 root root  7339 Jan  3 18:43 image-01.jpeg
-rw-r--r-- 1 root root  7345 Jan  3 18:43 image-02.jpeg
-rw-r--r-- 1 root root  6835 Jan  3 18:43 image-03.jpeg
-rw-r--r-- 1 root root  6835 Jan  3 18:43 image-04.jpeg
-rw-r--r-- 1 root root  6835 Jan  3 18:43 image-05.jpeg
-rw-r--r-- 1 root root  6840 Jan  3 18:43 image-06.jpeg
-rw-r--r-- 1 root root 15832 Jan  3 18:43 image-07.jpeg
-rw-r--r-- 1 root root 15832 Jan  3 18:43 image-08.jpeg
-rw-r--r-- 1 root root 15862 Jan  3 18:43 image-09.jpeg

Pipeline with jpegdec (libjpeg or libjpeg-turbo backend) produces correct result that can be viewed by imagemagick.

# GST_DEBUG=6 gst-launch-1.0 -qe multifilesrc location="image-%02d.jpeg" caps="image/jpeg,framerate=30/1" ! jpegdec ! multifilesink location="image-%02d.yuv" 2>gst.log

# display -size 640x480 -depth 8 -sampling-factor 4:2:0 -colorspace srgb image-00.yuv

Pipeline with omxmjpegdec (rpi-userland backend) produces incorrect result that can be viewed by imagemagick and has many artifacts.

# GST_DEBUG=6 gst-launch-1.0 -e multifilesrc location="image-%02d.jpeg" caps="image/jpeg,framerate=30/1" ! omxmjpegdec ! multifilesink location="image-%02d-omx.yuv" 2>gst-omx.log

# display -size 640x480 -depth 8 -sampling-factor 4:2:0 -colorspace srgb image-00-omx.yuv

Is it problem of gst-omx or rpi-userland?