Linux/TDA2PXEVM: Image data file (yuv or png) read and display

Jeong Lee

Part Number: TDA2PXEVM

Tool/software: Linux

Dear TI,

I want to read image data file (yuv or png) and display on monitor (HDMI).

I found there is a similar usecase which is null_src_dec_display usecase.
But null_src_dec_display usecase only supports mjpg or h.264.

What I have as a file on linux file system is yuv or png.
- png file is a normal png image file.
- yuv file is what I saved the ISP output as a binary file.
Camera bayer raw data is processed by ISP on TDA2Px and I saved the ISP output (SYSTEM_DF_YUV420SP_UV) as a binary file.

In case of using png, is there any png decoder in vision SDK?
In case of using yuv, how can I relate the yuv data to Diplay Link (or IPC OUT/IN Link)?

Please, give me any advice or help.

Best regards.

over 6 years ago

0 Shravan Karthik over 6 years ago

TI__Genius 14650 points

Hi Jeong,

We don't have a PNG library as part of VSDK, however there is an open source PNG decode library you may want to port in VSDK.
github.com/.../upng

It is possible to display a YUV image file to display. You need to set the display link properties to indicate this accordingly. You can refer to the display link properties set for the chains_lvdsVipSingleCam_SgxDisplay chain for more information.

If you define your use-case using the Vision-SDK use-case generation tool, the links are automatically connected using IPC. Please refer to the Vision-SDK Linux user-guide and the Vision-SDK_UsecaseGen user guide for more information.

Regards
Shravan

0 Jeong Lee over 6 years ago in reply to Shravan Karthik

Prodigy 50 points

Hello Shravan,

Thank you for the answer.

According to your suggestion (display link properties set in "chains_lvdsVipSingleCam_SgxDisplay"),
I defined usecase as below:
-------------------------
NullSource (A15) -> SgxFrmcpy (A15) -> Display
-------------------------

And I generated _priv.h and _priv.c using generation tool.

I also created .c file based on "null_src_decode_display" usecase (because of file input (nullsrc))
and "lvds_vip_single_cam_view_sgx_display" usecase.

But I encounted below run-time error.
================
ASSERT (sgxFrmcpyLink_drv.c|SgxFrmcpyLink_drvDoProcessFrames|392)
[HOST] [HOST ] 139.999328 s: SGXFRMCPY: ERROR: Recevied invalid buffer type !!!
================
This error occured because my yuv data is not type of SYSTEM_BUFFER_TYPE_VIDEO_FRAME or SYSTEM_BUFFER_TYPE_VIDEO_FRAME_CONTAINER.

In the sample usecase of "null_src_decode_display", chains_xxx_SetNullSrcPrms() function is defined as belows:
-------------
Void chains_xxx_SetNullSrcPrms(Chains_FileDisplayAppObj *pObj,
NullSrcLink_CreateParams *pPrm)
{
...
pChInfo->flags = System_Link_Ch_Info_Set_Flag_Buf_Type(pChInfo->flags,
/*SYSTEM_BUFFER_TYPE_VIDEO_FRAME*/
SYSTEM_BUFFER_TYPE_BITSTREAM);
...
}
-------------
If I change the flag from SYSTEM_BUFFER_TYPE_BITSTREAM to SYSTEM_BUFFER_TYPE_VIDEO_FRAME, another error happens.
(My yuv data is one frame data.)

How can I fix this problem?
Can you give any advice?

Thank you for your supports.

0 Subhajit Paul over 6 years ago in reply to Jeong Lee

TI__Expert 7015 points

Is there a reason why your data is bitstream and not video_frame? SGX links do not support bitstream data

0 Jeong Lee over 6 years ago in reply to Subhajit Paul

Prodigy 50 points

I just used the default value (SYSTEM_BUFFER_TYPE_BITSTREAM).
But anyway, I found another way to fix it.
Thank you for your concerns

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Linux/TDA2PXEVM: Image data file (yuv or png) read and display