Preview to fb1 ?

[texy]

Hi,
would it be possible to output the preview to framebuffer1 instead of the default output?
That way I could use one of my TFT display board to preview the camera's output
Texy

[texy]

Just bumping this thread. If anyone knows of a way, or is prepared to modify the raspistill/raspivid code to allow redirection of the preview to fb1, I'd be very grateful......
Texy

[jamesh]

I think that would require a copy - the preview is on its own dispmanx bitmap, so would need to be moved from there to the FB. I'm not sure how to do it. DOm might now, I'll try to remember to ask him Monday.

[dom]

The preview normally is handed entirely by the GPU (hence the few % arm utilisation when running).
Disaplaying on framebuffer would be expensive (in cpu) and is not trivial.

If you want it, then adapting something like raspiyuv to write the pixels to framebuffer is the solution.

[texy]

Sounds like it is quite feasible then, but beyond my capabilities...............................
T.

[cmegens]

Any ideas who could be able to do this?

[tasanakorn]

My program.

https://github.com/tasanakorn/rpi-fbcp

Just copy from /dev/fb0 to /dev/fb1 by vc_dispmanx_snapshot. It should display everything from primary display to fb1.

[texy]

Sounds great - can't wait to try it. What display did you use when developing, and what kind of framerate did you achieve?
I am assuming that this handles video as well as stills?

Texy

[tasanakorn]

I'm test with 2.8" 240x320 (Renesas R61505 flexfb SPI 60Mhz).

I did not measure framerate.
It take ~ 10ms to take screenshot and copy to framebuffer.
It enought to preview camera or play video with omxplayer (better than mplayer on framebuffer). I put 50ms delay in each loop to reduce cpu usage (now 1% cpu usage).

You can adjust it and share your result.

IMG_9814_s.jpg (33.55 KiB) Viewed 37050 times

The big problem right now is, I don't know how to sync to framebuffer refresh.

[texy]

Wow.
Got some quick instructions? Is it running as a background task and you use pi-cam commands as usual, or does your app control the pi-cam too?
Texy

[tasanakorn]

This app like normal app. but it does not output any text on console (some debug message send to syslog).
You can run with & to take it in background like.

> ./fbcp &

Before use this run this app. Make sure you are run lastest raspberry pi firmware (> 2013-07-11 with dispmanx_screeshort scale).
Beware, if you update firmware with rpi-update, It will replace kernel/module with official (I don't remember how to skip kernel update). Then test your framebuffer driver again (you might need to rotate screen to landscape to match with primary screen ratio)

build
------

$ git clone https://github.com/tasanakorn/rpi-fbcp.git
$ cd rpi-fbcp
$ mkdir build
$ cd build
$ cmake ..
$ make

Run
----

$ ./fbcp &

Check Log (if you want)
-------------

$ tail -f /var/log/message



Now. you should see primary screen on framebuffer device. At this point you can run any program (raspivid, raspistill, startx or omxplayer) like on primary screen (let me know if it not).

[texy]

This app like normal app. but it does not output any text on console (some debug message send to syslog).
You can run with & to take it in background like.

> ./fbcp &

Before use this run this app. Make sure you are run lastest raspberry pi firmware (> 2013-07-11 with dispmanx_screeshort scale).
Beware, if you update firmware with rpi-update, It will replace kernel/module with official (I don't remember how to skip kernel update). Then test your framebuffer driver again (you might need to rotate screen to landscape to match with primary screen ratio)

build
------

$ git clone https://github.com/tasanakorn/rpi-fbcp.git
$ cd rpi-fbcp
$ mkdir build
$ cd build
$ cmake ..
$ make

Run
----

$ ./fbcp &

Check Log (if you want)
-------------

$ tail -f /var/log/message



Now. you should see primary screen on framebuffer device. At this point you can run any program (raspivid, raspistill, startx or omxplayer) like on primary screen (let me know if it not).

I needed to

Code: Select all

sudo apt-get install cmake

as well, but I still get this error :

Code: Select all

pi@raspberrypi ~/rpi-fbcp/build $ make
Scanning dependencies of target fbcp
[100%] Building C object CMakeFiles/fbcp.dir/main.c.o
In file included from /opt/vc/include/interface/vcos/vcos_assert.h:149:0,
                 from /opt/vc/include/interface/vcos/vcos.h:114,
                 from /opt/vc/include/interface/vmcs_host/vc_dispmanx.h:33,
                 from /opt/vc/include/bcm_host.h:46,
                 from /home/pi/rpi-fbcp/main.c:8:
/opt/vc/include/interface/vcos/vcos_types.h:38:33: fatal error: vcos_platform_types.h: No such file or directory
compilation terminated.
make[2]: *** [CMakeFiles/fbcp.dir/main.c.o] Error 1
make[1]: *** [CMakeFiles/fbcp.dir/all] Error 2
make: *** [all] Error 2
pi@raspberrypi ~/rpi-fbcp/build $

[tasanakorn]

Sorry.. missing some include path.

Code: Select all

    $ cd rpi-fbcp
    $ git pull
    $ cd build
    $ cmake ..
    $ make
    

[texy]

Thankyou - that is working - and it is working very well with my display board boards on HY28A-LCDB.
I am sure that people will find this very useful,
Texy

[Aikidokajeff]

I sure will!
Although I'm currently tied up with work/family and trying to write a python interface so I can run without a keyboard etc.

Very cool, well done!

Jeff

[alexeames]

Thankyou - that is working - and it is working very well with my display board boards on HY28A-LCDB.
I am sure that people will find this very useful,
Texy

Fantastic news. Does it work well enough to use one of these little screens as a preview screen for video? That's the breakthrough I've been holding out for otherwise we're stuck with crappy car reversing screens on the composite RCA connector.

[texy]

Thankyou - that is working - and it is working very well with my display board boards on HY28A-LCDB.
I am sure that people will find this very useful,
Texy

Fantastic news. Does it work well enough to use one of these little screens as a preview screen for video? That's the breakthrough I've been holding out for otherwise we're stuck with crappy car reversing screens on the composite RCA connector.

...it most certainly does work well enough, at least with my 2.8"TFT boards. Because it now copies main output to fb1, it allows you to play video's with omxplayer at a far better framerate than direct just plain mplayer playback to fb1

In theory also raspbmc could be used with this screen...with a bit of tinkering.
Texy

[tvjon]

This app like normal app. but it does not output any text on console (some debug message send to syslog).
......
Now. you should see primary screen on framebuffer device. At this point you can run any program (raspivid, raspistill, startx or omxplayer) like on primary screen (let me know if it not).

Thank you kindly for sharing this tasanakom.

I'm not sure the tft display would be useful to me yet without it! I've had no luck with the python side of things so far (perhaps because the only python I know is Monty )

It appears that:
os.environ["SDL_FBDEV"] = "/dev/fb1"
is ignored by the test code, so the only way it will work is by having no display other than the tft.

It's rather impractical for my use to have to keep (un)plugging hdmi monitor, so your application means I can now view video & pictures.

You asked for feedback so here's a short lo-res video showing hdmi screen flashing when using:

raspivid -t 0

It only occurs on hdmi. The tft "mirroring" is flash-free.

That in itself is interesting, as yesterday when I first connected the tft display I had several hours of tft backlight flashing. Today however, it seems ok so far.

[tasanakorn]

...

You asked for feedback so here's a short lo-res video showing hdmi screen flashing when using:

raspivid -t 0

It only occurs on hdmi. The tft "mirroring" is flash-free.

That in itself is interesting, as yesterday when I first connected the tft display I had several hours of tft backlight flashing. Today however, it seems ok so far.

Hi. tvjon
Thank you for your feedback.

Recent code, I reduce delay between frame from 50ms to 25ms to increase update rate. I think it update too much. Because I use VideoCore to capture primary screen, It might interfere and slow down raspivid task.

Since I don't know anything inside VideoCore. I don't know how to avoid that.

Hope broadcom guy interest this thread and give me a hint.

[sharix]

Is it possible to use this to display the camera preview through SSH?

[texy]

Ssh is only a terminal device. You can send the fbcp command to start coping from main to fb1 via ssh, but the actual output remains with fb1.
Texy

[tvjon]

Yes, via ssh works fine

[texy]

Hi. tvjon
Thank you for your feedback.

Recent code, I reduce delay between frame from 50ms to 25ms to increase update rate. I think it update too much. Because I use VideoCore to capture primary screen, It might interfere and slow down raspivid task.

Since I don't know anything inside VideoCore. I don't know how to avoid that.

Hope broadcom guy interest this thread and give me a hint.

I have only downloaded and used the initial release - has this recent code been released, or only your own experiments?

Thanks again
Texy

[jamesh]

...

You asked for feedback so here's a short lo-res video showing hdmi screen flashing when using:

raspivid -t 0

It only occurs on hdmi. The tft "mirroring" is flash-free.

That in itself is interesting, as yesterday when I first connected the tft display I had several hours of tft backlight flashing. Today however, it seems ok so far.

Hi. tvjon
Thank you for your feedback.

Recent code, I reduce delay between frame from 50ms to 25ms to increase update rate. I think it update too much. Because I use VideoCore to capture primary screen, It might interfere and slow down raspivid task.

Since I don't know anything inside VideoCore. I don't know how to avoid that.

Hope broadcom guy interest this thread and give me a hint.

I think probably you will start to hit processor (The video scaler/compositor) and memory bandwidth issues with those low figures. That's a lot of data to be processing per second when added to the data requirements of the camera as well.

[PiGraham]

My program.

https://github.com/tasanakorn/rpi-fbcp

Just copy from /dev/fb0 to /dev/fb1 by vc_dispmanx_snapshot. It should display everything from primary display to fb1.

This is running great for me with Texy's 2.8" TFT module. Camera preview, omxplayer output, copying HDMI or composite (aka headless)

Thanks tasanakorn!