saLoopBack & graphic overlay

Binh Thai

Hi Everyone,

I'm working with the EZSDK (5.04.00.11) on the EVM-8168. My goal is to get a graphic application like the Matrix_GUI to be overlaid with transparency on top of the video displayed by the saLoopBack example in the EZSDK.

When I tried to run saLoopBack with the graphic plane turned on, I got a messed up display. I think the reason is because saLoopBack uses a buffer allocated by /dev/fb0 which is shared with the Matrix_GUI program. Am I correct?

Therefore, I tried to modify saLoopBack to allocate a different memory region. I did that by replacing the following call in setupBuffers()

buffer_addr[0] = (unsigned char *)mmap(0,
buffersize * MAX_BUFFER,
(PROT_READ | PROT_WRITE),
MAP_SHARED, fbdev_fd, 0);

by this call

buffer_addr[0] = (char*)malloc(buffersize * MAX_BUFFER);

However, at run time, I got the following errors:

VPSS_FVID2: contrl event 0x5 timeout
VPSS_FVID2: contrl event 0x10020003 timeout
ti81xxvin ti81xxvin: ti81xxvin_vps_create failed
ti81xxvin ti81xxvin: Vps create failed
VIDIOC_DQBUF
: Invalid argument
VPSS_FVID2: contrl event 0x10040018 timeout
VPSS_DCTRL: failed to get node input status
VPSS_FVID2: contrl event 0x10040018 timeout
VPSS_DCTRL: failed to get node input status
VPSS_VIDEO: Remove Video0 Edges failed

The buffer used in saLoopBack is of type V4L2_MEMORY_USERPTR. I should be able to queue application-allocated memory, right? What am I missing?

Thanks a lot,

Binh

over 13 years ago

0 Brijesh Jadav over 13 years ago

TI__Guru**** 476595 points

Hi,

One thing is you cannot use malloc for allocating physically continuous buffer, because malloc allocates the buffers from the user space, which cannot be used. since hardware needs physically continugous buffer.

Thanks,

Brijesh Jadav

0 HardikShah over 13 years ago in reply to Brijesh Jadav

TI__Mastermind 20245 points

Hi,

SaLoopback cant be run in parallel QT since saLoopback is trying to configure Framebuffer for its usage in saLoopback. Actually framebuffer in /dev/fb0 is used as userptr in saLoopback for capture driver. So you should stop QT first and than try to run saLoopBack.

Regards,

Hardik Shah

0 Subha Viswanathan over 10 years ago in reply to HardikShah

Intellectual 470 points

I have the same issue. I understand that saLoopBack cannot be used as it used Graphics Buffer. In that case, please help in what changes are required in saLoopBack to bring Graphics Overlay

0 Brijesh Jadav over 10 years ago in reply to Subha Viswanathan

TI__Guru**** 476595 points

why dont you use fb1 or fb2 in loopback if it is not used by qt?

Rgds,

Brijesh

0 Subha Viswanathan over 10 years ago in reply to Brijesh Jadav

Intellectual 470 points

I basically want Video to be in Video layer (/dev/video0). Does saMemDiaply help in this regard?

0 Subha Viswanathan over 10 years ago in reply to Subha Viswanathan

Intellectual 470 points

When I change the saLoopBack function to use /dev/db1, I get segmentatio Fault

Please provide your inputs

root@dm814x-evm:/usr/bin# ./saLoopBack
Driver Name: ti81xxvin
Driver bus info: TI81xx Platform
Driver is capable of doing capture
saLoopBack:
Mode set is 720P60
Driver Name:
Driver bus info: Ã@@`
=============================================================
Capture Format:
=============================================================
fmt.type = 1
fmt.width = 1280
fmt.height = 720
fmt.pixelformat = 1448695129
fmt.bytesperline = 2560
fmt.sizeimage = 1843200
=============================================================
=============================================================
Display Format:
=============================================================
fmt.type = 2
fmt.width = 1280
fmt.height = 720
fmt.pixelformat = 1448695129
fmt.bytesperline = 2560
fmt.sizeimage = 1843200
=============================================================
Segmentation fault

0 Subha Viswanathan over 10 years ago in reply to Subha Viswanathan

Intellectual 470 points

This is the code snippet I ahd changed

static int setupBuffers(void)
{
struct fb_fix_screeninfo fixinfo;
struct fb_var_screeninfo varinfo, org_varinfo;
int ret;
int buffersize;
int i;

/*Open FB device*/
fbdev_fd = open("/dev/fb1", O_RDWR);
if (fbdev_fd <= 0) {
perror("Could not open fb device\n");
return -1;
}

0 Margarita Gashova over 10 years ago in reply to Subha Viswanathan

TI__Guru* 80190 points

Hello,

Refer to :

http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/p/387258/1368025#1368025

Best Regards,
Margarita

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saLoopBack & graphic overlay