topic Re: 8M Plus H264 Encoding issues, unreliable firmware in i.MX Processors

8M Plus H264 Encoding issues, unreliable firmware

KrishnaraoP — Thu, 31 Jul 2025 11:10:26 GMT

Hi I am using 8M Plus SOM for my streaming application, using imx-gst1.0-plugin

My Linux version: 6.6.52-lts-next

Many issues observed, as per i.MX VPU Application Programming Interface Linux Reference Manual

when bitrate set to zero, nQuantParam used to control the QP, but it is not working.

When I set VPU_ENC_CONF_INTRA_REFRESH, VPU_ENC_CONF_RC_INTRA_QP API returning Success, but not reflecting in the encoded output.

Changed DEFAULT_STREAM_SLICE_COUNT to 4 in gstvpuenc.c, then getting following error

VCEncSetCodingCtrl: stream multi-segment core not supported
VCEncSetCodingCtrl: ERROR unsupported argument by HW
0:00:05.805982875 6326 0xffff88000f10 ERROR vpuenc gstvpuenc.c:987:gst_vpu_enc_open_vpu:<vpuenc_h264-0> opening new VPU handle failed: failure
0:00:05.806036375 6326 0xffff88000f10 ERROR vpuenc gstvpuenc.c:1191:gst_vpu_enc_handle_frame:<vpuenc_h264-0> gst_vpu_enc_open_vpu failed.

Can anybody from NXP, please point out the right VPU application manual for 8M Plus,

currently I am using https://www.nxp.com/docs/en/reference-manual/RM00294.pdf

Most of the stated encoded features in the manual are not working.

Re: 8M Plus H264 Encoding issues, unreliable firmware

Bio_TICFSL — Thu, 31 Jul 2025 14:00:05 GMT

Hello,

There is a problem in web site and there is no document for 6.6.52 however the VPU programming is practically the same as you describe, but you have an error where you might pass the argument on the VPU or the h264 has artifact or version incompatible.

Regards

Re: 8M Plus H264 Encoding issues, unreliable firmware

KrishnaraoP — Thu, 31 Jul 2025 14:40:41 GMT

Hi I checked the imx-vpuwrap library.

a) Not setting the QP parameter in VPU_EncEncodeFrame function

b) Not passing the parameters related to VPU_ENC_CONF_INTRA_REFRESH, VPU_ENC_CONF_RC_INTRA_QP in VPU_EncConfig function.

Due to this, unable to get proper results after setting the parameters in imx-gst1.0-plugin

Looks like the wrapper library is incomplete.

Re: 8M Plus H264 Encoding issues, unreliable firmware

KrishnaraoP — Sun, 03 Aug 2025 17:35:53 GMT

after digging further on imx-vpuwrap and imx-gst1.0-plugin, this issue not related to Linux version.

Only frame type and bitrate are configurable, but the VPU application programming manual and imx-gst1.0-plugin says differently.

Can anybody from NXP Techniacal team, please provide the alternative solutions.

Re: 8M Plus H264 Encoding issues, unreliable firmware

Tashia — Tue, 02 Sep 2025 09:39:42 GMT

Hi @KrishnaraoP I have updated a reply on the following ticket:

https://community.nxp.com/t5/i-MX-Processors/imx-gst1-0-plugin-VPU-Encoding-firmware-Issue-for-setting-the-QP/m-p/2149051/highlight/false#M239974

in case, you require further information, kindly let me know.

Kind Regards,

Tashia