Jepg_decode failes to decode grayscale jpeg

Hello. We have a camera that grabs data as color separated jpeg images. Therefor for each color I have a grayscale jpeg file. I’ve been trying to get the jpeg_decode working on the Xavier. The provided NvJpegDecode failed to decode the images with both options (–decode-fd and --decode-buffer). I have applied one of the patches found on the forum https://devtalk.nvidia.com/default/topic/1043325/jetson-tx2/nvjpeg-die-on-decoding-picture/ and I can now decdoe to buffer.

jpeg_decode num_files 1 ./1.jpg ./1.raw --decode-buffer
Image Resolution - 1232 x 1024
App run was successful

However the option --decode-fd still does not work.

jpeg_decode num_files 1 ./1.jpg ./1.raw --decode-fd
Failed to query video capabilities: Inappropriate ioctl for device
Unsupported color conversion request

I would like to have both options working, especially since decode to fd is supposed to be faster. Any help in getting it working is highly appreciated.

Looks like --decode-fd not support due to limit of HW alignment.

https://devtalk.nvidia.com/default/topic/1043325/jetson-tx2/nvjpeg-die-on-decoding-picture/post/5293469/#5293469

Is there any way to get this working? I need to decode 24 of these jpegs at 30 fps ? The best I can obtain now is 100 fps per image ( ~4 fps for all) using decode-buffer.

Hi,
Please attach a GRAY jpeg so that we can reproduce the failure.

Hi,
It is confirmed not supported. Please refer to
https://docs.nvidia.com/jetson/archives/l4t-multimedia-archived/l4t-multimedia-271/classNvJPEGDecoder.html

The JPEG decoder is capable of decoding YUV420, YUV422, and YUV444 JPEG images.

We will support GREY format in tegra_multimedia_api sample 12_camera_v4l2_cuda on r32.2. If your source is a USB camera, please wait for next r32.2.

Hello.

Thanks for the information. I am not sure whether it will help. My camera is an USB camera, but the data format is proprietary. The 24 jpgs are all a subpart of the buffer.

For completeness I have attached one of the jpg files. I hope that GRAY jpegs will be fully supported in the next release(s).