JPEG decoding/encoding squeezes the image

[praxidike97]

Hey all,

I have an issue with the JPEG decoding/encoding on the Orin NX. I used the examples from

/usr/src/jetson_multimedia_api/samples/05_jpeg_encode

and

/usr/src/jetson_multimedia_api/samples/06_jpeg_decode

with the provided image under

/usr/src/jetson_multimedia_api/data/Picture/nvidia-logo.jpg.

The problem here is that when I first decode this image and then encode it again the result (see lower image) does not exactly like the source image (see upper image). At first sight they look the same, but if you look closely, there is a small line of noise on the bottom of the encoded image, so that the whole image is a little bit squeezed. So my question is, am I doing something wrong?

[DaneLLL]

Hi,
For information, do you use Jetpack 5.1.3 or 6.0GA?

[praxidike97]

Hi,

wen I run cat /etc/nv_tegra_release it says that I have Jetson Linux 35.4.1 which I think means I have Jetpack 5.1.2.

[DaneLLL]

Hi,
We would suggest upgrade to Jetpack 5.1.3 and apply the prebuilt lib:

Jetson/L4T/r35.5.x patches - eLinux.org
[MMAPI/gstramer] NvJpegDecoder/nvjpegdec does not work properly

If you have to stay on 5.1.2, please use software JPEG decoder.

[praxidike97]

Ok thanks, I will try the approach with 5.1.3.

[praxidike97]

Ok, I tried exactly what you proposed (upgrade to 5.1.3 and use the different libnvjpeg.so) but the image is still wrong. Anything else to do to fix this?

[DaneLLL]

Hi,
If you run 05 sample to decode the JPEG and save to YUV, is the YUV data correct or not? Please help try it and share the result.