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by blackshard83
Tue Oct 17, 2017 10:31 am
Forum: Graphics programming
Topic: OpenCL on the VideoCore IV!
Replies: 82
Views: 58830

Re: OpenCL on the VideoCore IV!

Great job indeed!
Congratulations!
by blackshard83
Tue Oct 17, 2017 10:29 am
Forum: Graphics programming
Topic: EGL and OpenVG broadcom extensions, what they do?
Replies: 17
Views: 5148

Re: EGL and OpenVG broadcom extensions, what they do?

Yep, looks like the Ultibo OpenVG examples is based on AJStarkes code and that uses JPEGlib so it is probably not accelerated :( But who knows, you have to dig deep to find the real code and with so many layers I get confused. This in VGShapes.pas function VGShapesCreateImageFromJpeg(const filename...
by blackshard83
Mon Oct 02, 2017 7:35 am
Forum: Graphics programming
Topic: EGL and OpenVG broadcom extensions, what they do?
Replies: 17
Views: 5148

Re: EGL and OpenVG broadcom extensions, what they do?

I was exactly thinking about https://github.com/raspberrypi/firmware/blob/master/hardfp/opt/vc/include/EGL/eglext_brcm.h include header. Listing the official EGL extensions I get these ones: EGL_KHR_image EGL_KHR_image_base EGL_KHR_image_pixmap EGL_KHR_vg_parent_image EGL_KHR_gl_texture_2D_image EGL...
by blackshard83
Thu Sep 28, 2017 2:17 pm
Forum: Graphics programming
Topic: EGL and OpenVG broadcom extensions, what they do?
Replies: 17
Views: 5148

Re: EGL and OpenVG broadcom extensions, what they do?

Thanks for the answer, but it does not help. I was specifically asking some documentation about EGL and OpenVG broadcom extensions.
EGL and OpenVG libraries are well documented by khronos specifications available on their site for free
by blackshard83
Thu Sep 28, 2017 11:10 am
Forum: Graphics programming
Topic: EGL and OpenVG broadcom extensions, what they do?
Replies: 17
Views: 5148

EGL and OpenVG broadcom extensions, what they do?

I see that in /opt/vc/include egl and openvg directories there are some import header files dealing with some broadcom specific extensions to EGL and OpenVG, but I can't find any documentation about them. I'm curious about what they do and if can be generally useful. I guess that most probably they ...
by blackshard83
Tue Sep 26, 2017 11:51 am
Forum: Graphics programming
Topic: How to free unused dispmanx layer (in case of SIGSEGV)
Replies: 7
Views: 3036

Re: How to free unused dispmanx layer (in case of SIGSEGV)

AFAIK there is no documented way for a process to get the handle to a dispmanx layer of another process, so you can't free it after the leak. Though I never tried to store the dispmanx handles somewhere (maybe on the filesystem) and let another process pick them up and do the calls to free them. Fro...
by blackshard83
Tue Sep 26, 2017 11:38 am
Forum: Graphics programming
Topic: OpenVG & vgWritePixels
Replies: 13
Views: 4069

Re: OpenVG & vgWritePixels

It looks weird to me too, you should "just" see the colors altered if you fail to match the channels from the source image to the OpenVG format. Nonetheless it could be tricky because if you map a color channel to the alpha channel you may actually miss some parts of the image because the color chan...
by blackshard83
Thu Sep 07, 2017 10:01 am
Forum: Troubleshooting
Topic: Recipe to freeze the VideoCore (and freeze on reboot)
Replies: 0
Views: 254

Recipe to freeze the VideoCore (and freeze on reboot)

Hello, I don't know if this is a news or it is well-known, but I found a way to freeze the VideoCore and make the ARM unable to reboot. issuing: vcgencmd set_logging level=128 and then running any video using the omxplayer will flood the VideoCore log and bring the GPU to its knees. Unfortunately th...
by blackshard83
Thu Mar 23, 2017 7:48 am
Forum: OpenMAX
Topic: audio_render time latency
Replies: 3
Views: 2916

Re: audio_render time latency

No, I didn't. My basic block is a simple audio rendering driver, just a little piece of code that outputs some raw audio. In my experience, usually you program the audio consumer part (the audio_render component, in this case) with the latency you want (in terms of buffers/samples) and then the cons...
by blackshard83
Wed Mar 22, 2017 4:50 pm
Forum: OpenMAX
Topic: audio_render time latency
Replies: 3
Views: 2916

Re: audio_render time latency

Hmmm, I guess I got it wrong: my initial thought was that I had to feed the omx component as soon as every buffer is completed, so I have a semaphore which is increased as soon as a buffer is done, catching the EmptyBufferDone callback. This is not ideal because, I realize, the buffer is emptied imm...
by blackshard83
Tue Mar 21, 2017 4:33 pm
Forum: OpenMAX
Topic: audio_render time latency
Replies: 3
Views: 2916

audio_render time latency

Hi all, I'm not sure if there's already an answer, I could not find any googling around. Related to my old forum post (https://www.raspberrypi.org/forums/viewtopic.php?f=70&t=175450), I would like to know what is the latency, in milliseconds or samples, added by audio_render OMX component? I see tha...
by blackshard83
Thu Mar 02, 2017 11:01 am
Forum: OpenMAX
Topic: ALSA driver uses audio_render component?
Replies: 1
Views: 2616

Re: ALSA driver uses audio_render component?

Just for knowledge:

I discovered, digging into raspberry kernel fork, that the driver bypass the OMX components, hence reduces the latency of the stream
by blackshard83
Fri Feb 24, 2017 3:01 pm
Forum: OpenMAX
Topic: ALSA driver uses audio_render component?
Replies: 1
Views: 2616

ALSA driver uses audio_render component?

As per subject, I'm facing the HDMI DMA issue and would like to understand what is the way ALSA uses to render the output. My guess was that it was using the audio_render OMX component, but after some tests I made I'm not so sure about. Also the audio_render component is forced to pass through the a...
by blackshard83
Fri Feb 10, 2017 3:38 pm
Forum: OpenMAX
Topic: ffmpeg & h264_omx on pi3 very slow
Replies: 15
Views: 26408

Re: ffmpeg & h264_omx on pi3 very slow

Don't expect miracles, the h264 hardware encoder is pretty basic and produces very low quality output even at high bitrates, and software encoding is still very slow on ARM machines.
by blackshard83
Fri Jan 27, 2017 1:22 pm
Forum: OpenMAX
Topic: Shared state bug in audio_render when output is HDMI
Replies: 2
Views: 2744

Re: Shared state bug in audio_render when output is HDMI

Ok fine, thanks a lot. So now I'm in the people asking for a fix :(
by blackshard83
Fri Jan 27, 2017 12:49 pm
Forum: OpenMAX
Topic: Shared state bug in audio_render when output is HDMI
Replies: 2
Views: 2744

Shared state bug in audio_render when output is HDMI

Hello, I'm trying to run multiple omxplayer instances but I noticed a problem that only happens when output is set to "omx:hdmi" that probably relates to some shared state in omx components or firmware. The following commands starts two omxplayer instances with two video side by side, you should run...
by blackshard83
Fri Jul 08, 2016 2:48 pm
Forum: OpenMAX
Topic: Multicore bugs in OMX video components fixed lately?
Replies: 3
Views: 2561

Re: Multicore bugs in OMX video components fixed lately?

I really appreciate your answer pointing me to the issues, thank you! Apparently it looks really similar to https://github.com/raspberrypi/firmware/issues/449, but the OP says that his problem is more severe on pi1 than pi2, instead mine happens only on pi2. I'll double check the discussions. My pla...
by blackshard83
Fri Jul 08, 2016 8:33 am
Forum: OpenMAX
Topic: Multicore bugs in OMX video components fixed lately?
Replies: 3
Views: 2561

Multicore bugs in OMX video components fixed lately?

Hello, I get strange, sporadic and unreplicable issues when running videos with a modified omxplayer on raspberry pi 2 models. Practically the video gets stuck on a frame and audio stops, sometimes the time goes on (given by a OMX Scheduler component), sometimes also the time freezes. The system is ...
by blackshard83
Mon Jun 27, 2016 10:10 am
Forum: General discussion
Topic: [raspbian]Mix older kernel with newer firmware
Replies: 2
Views: 614

Re: [raspbian]Mix older kernel with newer firmware

Thanks for pointing me the github issue.

Unfortunately my kernel resides on a read only squashfs custom root filesystem which should be rebuilt and distributed to several remote devices. I prefer to avoid the kernel upgrade until it is really necessary.
by blackshard83
Mon Jun 27, 2016 7:48 am
Forum: General discussion
Topic: [raspbian]Mix older kernel with newer firmware
Replies: 2
Views: 614

[raspbian]Mix older kernel with newer firmware

As the subject suggests, is it safe to mix an older raspbian kernel (3.18) with newer firmware files (start.elf, mainly)? I noticed that an older firmware I was using brought the hardware decoder into unstable state in case of 4:2:2 h.264 videos, due to lack of proper hardware decoding capacity. The...
by blackshard83
Tue Jun 21, 2016 6:53 am
Forum: OpenMAX
Topic: Bug in OMX audio render component?
Replies: 3
Views: 2478

Re: Bug in OMX audio render component?

Thanks, got it. I tried with more instances and found that the limit has been raised.
I wonder the bcm2805 ALSA driver do use a slot or not...
by blackshard83
Mon Jun 20, 2016 2:31 pm
Forum: OpenMAX
Topic: Bug in OMX audio render component?
Replies: 3
Views: 2478

Re: Bug in OMX audio render component?

All my fault: the problem seems to disappear upgrading to latest kernel and firmware; multiple audio_render instances seems to work fine now, even when in use with omxplayer.
I'll stress a bit the system though to be sure it satisfies my needs.
by blackshard83
Mon Jun 20, 2016 12:55 pm
Forum: OpenMAX
Topic: Bug in OMX audio render component?
Replies: 3
Views: 2478

Bug in OMX audio render component?

I tried to run more than one instance of hello_audio to verify how many separate instances of audio_render components can be running in different processes at the same time. It turns out that more than three instances cause severe problems to the whole VideoCore IV system I launched hello_audio thre...
by blackshard83
Fri Jun 17, 2016 9:10 am
Forum: OpenVG
Topic: Call for review: fixing OpenVG wrapper library reliability
Replies: 6
Views: 12646

Re: Call for review: fixing OpenVG wrapper library reliabili

Good initiative! I've been using OpenVG since the launch of the first Pi and GPU memory corruption was an issue then and now (Jessie Lite - RPi-2). My approach is similar to yours with a thin C++ wrapper library (including vector fonts) on top of the OpenVG API. Errors show up as damaged fonts (ove...
by blackshard83
Mon Jun 06, 2016 3:17 pm
Forum: OpenMAX
Topic: Hacking the source code of the omxplayer
Replies: 2
Views: 3723

Re: Hacking the source code of the omxplayer

Probably you can't just do that in the omxplayer because the omxplayer doesn't know when the new frame is rendered. Actually the omxplayer just feeds the OMX video decoder component which is in turn connected (tunnelled) to OMX render component and timing is given by an OMX scheduler. So the omxplay...

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