AM62A7: Can I take in a CSI data stream at 4k60 and encode it using the H.265 video encoder?

Hello David,

Your understanding about VPAC capability is correct. Before we check the encoder capability, l'd like to remind you that:

1. the CSI bandwidth is 1.5Gbps per lane. So the total bandwidth is 6Gbps with 4 lanes. That means your video data bit width needs to be less than 12-bit per pixel.
2. you need to use an image sensor which has built-in ISP and outputs YUV/RGB data.

Assuming you are okay with the above, let me pass the encoder question to our H.265 expert.

Regards,

Jianzhong

Hi David,

On AM62A7 max resolution that is supported for video encoding in H.264/HEVC is  4k@30fps  as stated in the TRM.

Best Regards,

Suren

Hello Suren

Thanks for your reply - can you point me to the section of the TRM that states this?

When I read the TRM (spruj16b.pdf) I found this statement on p506:

7.4 Video Encoder/Decoder (VENC/VDEC) The following sections describe the video accelerator details for the device.

7.4.1 Introduction

The Video Accelerator is a 4K codec that supports both HEVC and H.264/AVC video formats. It provides high performance encode and decode capability up to 8bit 4K@60fps with a single-core architecture. The Video Accelerator can encode and/or decode any resolution up to 8192 x 4320. It guarantees real-time performance for encoding/decoding 4K 60fps based on its sophisticated, latency tolerant hardware architecture. The Video Accelerator is highly optimized for memory bandwidth loading and excellent power management.

This seems to contradict your assertion that the TRM says it can only do 4K@30fps.

Best regards

Dave

Hi David:

Screenshot:

Best Regards,

Suren

Thanks Suren

Directly above the highlighted line there is a statement:

- Encode and decode up to 8-bits 4K@60fps

This matches the statements in section 7.4 of the TRM but it is a bit strange that the headline figure in the overview section 1.4.25 from your screenshot above is only 4k30 - perhaps it is referring to applications where the video is also processed through the VPAC?

I'm back to the original question of whether 4k60 can be encoded if the VPAC is not used.

Best regards

Dave

David,

Video Encode and Decode are part of the Video Processing Hardware Accelerator on AM62A. VPAC is another Hardware accelerator.

I just ran this pipeline that doesn't include VPAC and I was able to encode/decode 4k 30 fps stream on AM62A.

Example pipeline:

gst-launch-1.0 videotestsrc is-live=true do-timestamp=true num-buffers=500 ! video/x-raw, width=3840, height=2160, framerate=30/1, format=NV12 ! v4l2h264enc ! filesink location=4k.h264

Best Regards,

Suren

Hello Jianzhong

After helpful discussion below with Suren I have taken a closer look at the Sony IMX678 sensor we are proposing to use and it states it can provide RAW10 or RAW12 via the CSI channel - would this meet your requirement above that I need to use a sensor with built in ISP and outputs YUV/RGB data?

If so then I can ask Suren if RAW10 can be encoded at 60fps - 12bit is OK at 30fps as he states below.

Best regards

Dave

Hi Suren

Thanks for this, the fact that it is a 12bit data stream has helped answer some other questions I had.  As some final questions could you comment on the following please?

The VPAC states it is capable of 315MPixels/s.  Does this mean that it could be used for the 4k30 NV12 stream you describe or is the 315MPixels/s dependent on bit depth?

Does the VPAC support RAW10 format? The TRM states only 8bit, 12bit, 14bit and 16bit are supported.

Many thanks again for your help.

Dave