Reasons for encLink dropping frames

Jayakrishnan

Expert 2790 points

Other Parts Discussed in Thread: DM388

S/W: IPNC RDK ver 3.8

Platform : dm388

Problem : encLink is dropping frames and not sending to encoder , because no output buffers are available.

One such issue is described here: http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/t/351375

I am facing the problem more seriously. It is continuously dropping 15 frames/sec, effectively reducing my encoder o/p fps to 30.

This happens when there is a delay in submitting frames to EncLink_codeSubmitData() function.

To verify this, I have introduced some delay in EncLink_codecProcessData() function after call to EncLink_codecQueueFramesToChQue() and before

calling EncLink_codecSubmitData().

I want to know why such a delay causes the output buffer being not available and hence causing the frames to drop.

Is there a way to fix this? In my case, I cannot avoid the delay.

Best Regards

over 10 years ago

0 Margarita Gashova over 10 years ago

TI__Guru* 80190 points

Hello,

I will notify the IPNC team for help.

BR
Margarita

0 Anand Kulkarni71405 over 10 years ago in reply to Margarita Gashova

TI__Expert 8920 points

Hi,

The VLIB APIs are getting used by the DMVA lib and we are not directing using the VLIB APIs in the IPNC RDK.

regards,

Anand

0 Jayakrishnan over 10 years ago in reply to Anand Kulkarni71405

Expert 2790 points

Hi Anand,
Can you elaborate a bit more? You mean VLIB APIs are responsible for Outbut Buffer being not available? Where are those APIs called?
Best regards
JK

0 Anand Kulkarni71405 over 10 years ago in reply to Jayakrishnan

TI__Expert 8920 points

Hi,

I am sorry ! the VLIB reply is not intended reply for your post.

Pl. ignore it.

regards,

Anand

0 Jayakrishnan over 10 years ago in reply to Anand Kulkarni71405

Expert 2790 points

Hi Anand
That's alright ! Can you look into this issue? You have already analyzed the 'output buffer not available ' issue and made fix in the kernel.
I have no problem, when trying to sync 3 channel inputs and giving it to codecSubmitData(). When I try to sync 4 channels, this outBuffer issue appears after running 1 hour or so.

Best regards
JK

0 Anand Kulkarni71405 over 10 years ago in reply to Jayakrishnan

TI__Expert 8920 points

Hi,

The post you are referring to here is not relevant one.That was for fixing the video freeze during SD card removal.

Coming back to your issue,if i put the delay between theEncLink_codecQueueFramesToChQue() and EncLink_codecSubmitData() calls using Task_sleep() then based on the amount of delay the input frames available will be more when you get the full frames from the previous link (System_getLinksFullFrames()) and when you try to submit multiple frames at the same time then the output queue may not have enough output buffers which will result in output buffer not available condition.

What is the delay you are introducing?

regards,

Anand

0 Jayakrishnan over 10 years ago in reply to Anand Kulkarni71405

Expert 2790 points

Hi Anand,

I had a freezing issue, almost every 4 minutes for a short duration. After using your uImage, it disappeared.

Coming back to my current issue, I put a delay of 40 msec. In this case, there is a frame drop of 15 fps, due to output buffer not available.

Because I am trying to sync 4 channel inputs, the delay comes around 30 msec. (This is, after trying lot of usecases).

With this there is no immediate output buffer issue. But after 1 hour ( sometimes after 3 hours) , the output buffer issue comes up, causing the fps to drop to 15.

Now , because I cannot decrease this delay further, the next possible thing is to increase the number of buffers in the output queue.

Currently it is 6 with each buffer size(outQueInfo->buf_size[0]) = 0x2A5580 ( 1920x1088 + 960x544 + 480x272 + 240x136). I tried increasing this number. But of no use. (Using only one pool)

Am I doing correct?

Best Regards

0 Anand Kulkarni71405 over 10 years ago in reply to Jayakrishnan

TI__Expert 8920 points

Hi,

If i put a delay of 40 msec, i can see the output buffer non-availability very quickly and the reason is that due to the delay the input frames get accumulated and there are not enough output buffers avaliable in the outQue.

The output buffer switching mechanism is that the full buffers are put in the outQue's fullQue and then the next link is notified and when the next link returns back the empty buffers they are put into the outQue's emptyQues. The full buffers are consumed by the IPCBitsIn link running on A8 and it is the one who is going to put the empty buffers back to the emptyQues.

You should check this loop to figure out the issue.

regards,

Anand

0 Jayakrishnan over 10 years ago in reply to Anand Kulkarni71405

Expert 2790 points

Hi Anand,

Your observations are correct. The delay causes input frames to get accumulated. After taking care of this, there is no output buffer problem , the frame rate is constant @ 30fps. Thanks a lot for the help.

Best regards

0 user3989101 over 8 years ago in reply to Jayakrishnan

Prodigy 60 points

Can you tell me how to deal with this problem?

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Reasons for encLink dropping frames