jpegenc is ignoring pixel-aspect-ratio
jpegenc seems to be ignoring the
pixel-aspect-ratio information from the caps, which can be a problem for non-square pixel ratios.
I found this bug trying to export JPEGs from a camera with a SAR of
95:112, even though the caps were correct in my GStreamer pipeline:
@ndufresne could reproduce the problem earlier on IRC:
did a quick test here, and jpegenc seems to present some bug
if I save a jpeg to disk with S/PAR 4:3, and then call gst-disoverer-1.0 -v test.jpg, it says the PAR is 1/1
if I use ffprobe, it says Stream #0:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 320x240 [SAR 1:1 DAR 4:3]
As he suggested, a workaround for now is to add
videoscale ! video/x-raw,pixel-aspect-ratio=1/1 after the decoder to force using square pixels.