Go to advanced search

by mdoe
Fri Sep 23, 2016 7:53 am
Forum: OpenMAX
Topic: OMX_VIDEO_PARAM_QUANTIZATIONTYPE
Replies: 3
Views: 3096

Re: OMX_VIDEO_PARAM_QUANTIZATIONTYPE

Thanks 6by9 :D Can I bounce an idea off you please? I've been playing with the quantization parameters in Intels Quicksync hardware encoder, I found that depending on source input you can more or less constrain the resulting bitrate of the output stream. That is, when you know what type of input (ac...
by mdoe
Thu Sep 22, 2016 6:07 pm
Forum: OpenMAX
Topic: OMX_VIDEO_PARAM_QUANTIZATIONTYPE
Replies: 3
Views: 3096

OMX_VIDEO_PARAM_QUANTIZATIONTYPE

I was wondering if anyone is able to tell me if OMX_VIDEO_PARAM_QUANTIZATIONTYPE is available to use with AVC encoding? I gather from snippets on other forums that with rate control disabled, OMX_IndexParamVideoQuantization can be used for QpI and QpP , but before I went down that road, knowing that...
by mdoe
Sat Sep 10, 2016 9:53 am
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

Re: OMX_Video_ControlRateVariable

That is an easy one :lol: I take it they disabled in the hardware? I was hoping it would afford me some more efficiency, but no matter. Is there a list of all the options that are disabled? I've discovered that the ffmpeg implementation adjusted the nPFrames by -1 relative to the defined GOP size, w...
by mdoe
Sat Sep 10, 2016 7:23 am
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

Re: OMX_Video_ControlRateVariable

Hello again :) Thanks to your help I've spent the last few days playing around with the parameters in OMX_VIDEO_PARAM_AVCTYPE, I've come to the conclusion constant rate control doesn't appear to work on any profile/level, you can enable it without the encoding process stalling, but it has no effect ...
by mdoe
Wed Sep 07, 2016 3:16 pm
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

Re: OMX_Video_ControlRateVariable

I've just noticed that the OMX_Video_ControlRateConstant is working even when I set the profile to main in the hello_encode, it's not hanging like before, odd. CABAC is probably nothing for me worry about, the ability to switch profiles was the most important thing, if that's working with CBR, even ...
by mdoe
Wed Sep 07, 2016 2:03 pm
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

Re: OMX_Video_ControlRateVariable

6by9, very kind of you to offer some code, that's a great help, thank you. I've been tinkering this morning/afternoon and have the following code working in the hello_encode OMX_VIDEO_PARAM_AVCTYPE avcParams; // set current bitrate to 1Mbit memset(&avcParams, 0, sizeof(OMX_VIDEO_PARAM_AVCTYPE)); avc...
by mdoe
Tue Sep 06, 2016 7:33 pm
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

Re: OMX_Video_ControlRateVariable

6by9, thank you for taking the time to find and post those links, my Google-fu failed me this time. That explains why the output was always H264 High 4.0 and I couldn't work out how to change it. So essentially, the code needs to be changed to instruct the encoder to use a baseline profile, that way...
by mdoe
Tue Sep 06, 2016 3:06 pm
Forum: OpenMAX
Topic: OMX_Video_ControlRateVariable
Replies: 10
Views: 4394

OMX_Video_ControlRateVariable

Hi rpi forum, As a bit of background I've been playing with the hardware video encoder in conjunction with an rtmp service, for the most part this has gone well, but I've been unable to constrain the bitrate of the video output to any real degree of success. I am not a developer of any sort, so plea...

Go to advanced search