jpeg decoder issue

Dear codec designer,

Can you reproduce the issue? I have resized the image to 720x480, it has the same issue. It seems the jpeg decoder can not decode

YUV444 image to RGB 24 bits properly.

Thanks,

Kaijun

Sorry for the delay, the person who can reply to was on leave. You should get a reply by tomorrow.

regards

Yashwant

Hi Kaijun,

Can you please share

(1) Testparams thats been set (Please efer to TestParams.cfg used in userguide or release package for all params name)

(2) Encoded image in .jpg format (Attached above image is in .bmp format)

Thanks,

Roopesh

Hi Roopesh,

1) I use gstreamer-based app. to test jpeg rather than the jpeg test program. it is nothing to do with TestParams.cfg.

2) I double checked the test image header bytes, It is jpeg, and ffmpeg shows

Input #0, image2, from '14.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: mjpeg, yuvj444p, 1280x720 [SAR 72:72 DAR 16:9], 25 tbr, 25 tbn, 25 tbc

How did you get bmp format?

Hi Roopesh,

1) I use gstreamer-based app. to test jpeg rather than the jpeg test program. it is nothing to do with TestParams.cfg.

2) I double checked the test image header bytes, It is jpeg, and ffmpeg shows

Input #0, image2, from '14.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: mjpeg, yuvj444p, 1280x720 [SAR 72:72 DAR 16:9], 25 tbr, 25 tbn, 25 tbc

How did you get bmp format?

Regards

Kaijun

Hi Kaijun,

Thanks for the info. On trying to save the image, it gets stored only in .bmp format. Can you please share .jpg as an attachment?

Thanks,

Roopesh

Hi Roopesh,

The previous jpeg image was attached, there is no other attachment way.

I looked at the test files in the jpeg codec. They use IJPEGDEC_* data structure, but they are casted to IMGDEC1_*, then passed to codec engine API. I use the Dmai API, it uses

only IMGDEC1_*, then passed to codec engine. I just wonder if the jpeg decoder needs extra data in  IJPEGDEC_* data structure.

Hi Kaijun,

IMGDEC_ is base structure for Image decoder object with minimal fields whereas IJPEGDEC_ is extended one with more fields available in it. IMGDEC_ is one of the fields in IJPEGDEC_ structure. Hence IJPEGDEC_ needs extra data as it is larger structure compared to IMGDEC_ structure.

Thanks,

Roopesh

The issue has nothing to do with IJPEGDEC_ structure. The decoder works with 720x576 without using IJPEGDEC_.

Kind Regards

Kaijun

Hi Yashwant,

Any progress?

KR

Kaijun