Go to advanced search

by perfo
Thu Mar 14, 2019 8:35 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Re: Shutter Glasses

I'm not getting any tearing though so the frame vs refresh can't be that far out of sync...
Is there any way to force the fps and refresh to be in sync ?
by perfo
Thu Mar 14, 2019 8:33 am
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Re: Display image as fast as possible

Problem with me is I believed the hype about basic and vba / visual basic being the future when MS decided to include it in there packages. I started with C , fortran , pascal and the usual crew but dropped them 30 years ago.. Not that I was particularly good then but my older brain has difficulty g...
by perfo
Wed Mar 13, 2019 9:32 pm
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Re: Display image as fast as possible

Nope still no closer.
Is there a way python can render images using the GPU ? Maybe some sort of MMAL interface that hides all the complexities from me ?
by perfo
Wed Mar 13, 2019 7:22 pm
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Re: Display image as fast as possible

Ah penny dropped about Jpegs.. there isn't a way to present a Jpeg in your example. It has to be de coded in to a memory location first and the memory location sent to the renderer. So Off to read more on how to use a Image_decoder to get the jpeg in the right format. Still none the wiser what to do...
by perfo
Wed Mar 13, 2019 6:27 pm
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Re: Display image as fast as possible

being Pi specific isn't a prob at all as that's where I'm hoping to do it all. I've been digging around the MMAl business for a few hours and not a lot further on than when I started :-( I had a look at that example you kindly provided but can't work out for the life of me where I'd stick in a Jpeg ...
by perfo
Wed Mar 13, 2019 4:48 pm
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Re: Display image as fast as possible

Nope, I'm not brought in to any particular way, as long as I can do it.. I'll go away and read up on MMAL. If I'm understanding it right are you saying MMAL doesn't use hardware acceleration and yet still manages 60fps or more ? That's impressive.. Ok off to read , thanks for the tip. I'll report ba...
by perfo
Wed Mar 13, 2019 10:08 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Re: Shutter Glasses

Grrr, It doesn't work. Looking at the Vsync on my scope I can see a nice train of pulses. With my code above this gets swapped to a nice square wave with the pulse going on with one Vsync pulse and going off with the next sync pulse. At a 60hz refresh rate these pulses are 16 ms so equal to 60 frame...
by perfo
Wed Mar 13, 2019 9:52 am
Forum: OpenMAX
Topic: Display image as fast as possible
Replies: 7
Views: 5369

Display image as fast as possible

I'm trying to display a series of still images as fast as possible. Hoping for 60fps or more. I can use any image format if one is preferable to others (involves less decoding maybe) So a few questions really. Is OpenMAX going to be the way to go ? I may be way off beam here but I'm thinking as omxp...
by perfo
Sun Mar 10, 2019 2:58 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Re: Shutter Glasses

Well thanks for all your comments folk :-) I've included what I've found incase it helps someone else. I finally discounted most avenues as they didn't keep in sync or gave other problems . The DPI and HDMI can be set up to mirror one an another and makes it easy to grab the Vsync off the GPIO but t...
by perfo
Wed Mar 06, 2019 3:10 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Re: Shutter Glasses

There is a great tut on stop motion film making here https://projects.raspberrypi.org/en/projects/push-button-stop-motion Using the code from there avconv -r 10 -i animation/frame%03d.jpg -qscale 2 animation.h264 to make a file out of my frames and then omxplayer animation.h264 to play it This works...
by perfo
Wed Mar 06, 2019 2:57 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Re: Shutter Glasses

I've done a bit of reading up on stop motion photography. This kind of application would be perfect for my needs as I simply need to show one image after another but in quick succession. However I can't seem to find a good tut on how to show a series of frames or images with the PI. Does anyone know...
by perfo
Tue Mar 05, 2019 4:20 am
Forum: Graphics, sound and multimedia
Topic: Shutter Glasses
Replies: 12
Views: 1790

Shutter Glasses

Hello All, I'm hoping someone out there may have some pointers as to the best approach for this project of mine. I'm using a pair of shutter glasses and hacked it so the RPI can control the glasses direct which is pretty simple. I would like to switch between two images then toggle an output pin. So...
by perfo
Thu Jan 05, 2017 5:47 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

In reply to ewanpth Could it be you are either not clearing some variables or buffers and thus compounding the numbers or maybe as you are delaying things is the reading not being taken over the full (right) set of data bits ? Did anyone have a go connecting these cheap things together to make a lon...
by perfo
Thu Dec 10, 2015 5:09 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Ah yes makes sense..
by perfo
Sat Dec 05, 2015 9:54 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

One step even easier then...thanks..
by perfo
Fri Dec 04, 2015 9:30 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

I think what he means is do a check on the clock pulse ... Ie if the clock pulse is high (or low depending on which state you are looking for) do a while loop until it changes state. Whilst in the while loop have a counter increment. At the end of the while have a look at the counter and if it is lo...
by perfo
Sun Oct 18, 2015 11:55 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Ok thanks. I have already ordered soem from hong kong and hoped they would eb the same but If I can get mine to work at least I know where to go to get one that does.. I've got two of these http://www.ebay.co.uk/itm/271993321208?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT £6.90 for tw...
by perfo
Sun Oct 18, 2015 9:35 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

What actual model of Caliper did you use Joan ?
by perfo
Wed Oct 14, 2015 12:13 pm
Forum: Automation, sensing and robotics
Topic: Tracking movement of game pieces on a board
Replies: 14
Views: 6556

Re: Tracking movement of game pieces on a board

The reed switch idea works of course but relies on a memory map in the controller to know where the pieces are it will know a piece is on this square but which piece is there will be unknown. Unless you could use maybe five reed switches under each square and identify the 32 pieces with a binary sig...
by perfo
Tue Oct 13, 2015 12:55 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Thanks good to know....
by perfo
Mon Oct 12, 2015 7:42 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

If the axis is moved quick the display on the caliper lags but then catches up ? Is that what you found? What about the PI though? If i'm understanding it right the caliper sends out a relative position from some arbitrary start point and thus even if the PI missed a load of data then it would still...
by perfo
Mon Oct 12, 2015 12:40 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Had another one of them thoughts. Would the PI be able to handle three axis then ?
Do the readers offer any sort of buffering ? If someone moved the scale too fast would it miss a few steps or catch up on next read ?
Thanks...
by perfo
Mon Oct 12, 2015 12:37 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Thanks for that, Perfect bit of investigation work.. I would have replied sooner and offered my thanks but somehow I got locked out of this here forum. Still I'm back and giving thanks... Now I'll definitely have to buy some and see if I can link them together multiple 300mm ones for a couple of £ e...
by perfo
Thu Sep 17, 2015 8:14 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

Thanks for the link. I guess I'm going to have to buy a few and play then.
by perfo
Sun Sep 13, 2015 2:16 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: interface with digital calipers
Replies: 52
Views: 13211

Re: interface with digital calipers

yep that's what I'm worried about but haven't enough knowledge to be definitive...

I had seen that tutorial but really I was hoping for a complete project with a software example I could try and figure out...

Go to advanced search