OctoWS2811 flicker

are you certain that you are using the most recent version OctoWS2811? As jimparis has pointed to, this was the route cause of much head scratching by a number of people a while ago. The copy for download was not updated, so check the version. You should be on Version 1.1. Deleting old and adding this resolved the flicker for me and others.
https://www.pjrc.com/teensy/td_libs_OctoWS2811.html
 
Hello Paul Stoffregen, thanks for the project Freescale Demo 3.ino I assembled board 88X48 = 4224led i have everything worked out, but there are questions about how to change the brightness? too dark to show the movie. whether it is possible to create one project for 8448 and more from SD Thank look forward to hearing
 
PaulStoffregen said:
Yes. In fact, since it'll probably be a while until I get around to "cleaning it up" for a proper release as OctoWS2811 version 1.2, I'm going to just dump all the raw, ugly Maker Faire code right here, right now!

This is for a demo to be shown in Freescale's booth. A few weeks ago they contacted me and wanted some way to showcase stuff people have made with their chips. I offered to build them a LED display if they covered the costs. So when you see references to stuff about Freescale, that's why.

First, here's the Teensy hardware. It's just the OctoWS2811 adaptor and WIZ820+SD adaptor we sell, soldered together with long pins.

View attachment 1970

Actually, what you can't see is pin 4 is cut between the Teensy and WIZ820+SD, and between the WIZ820+SD and Octo board, pins 3 and 4 are shorted together. This routes the SD card's CS signal to pin 3. You can see SD.begin(3) in the code, but I want to be clear this tiny hack is needed. You can't use pin 4, because it's reserved for OctoWS2811.

I should also mention, this is using a work-in-progress version of OctoWS2811, which you can get from github.

https://github.com/PaulStoffregen/OctoWS2811

Version 1.1 can't work together with the audio library, so you must use this newer code which fixes that issue.

On the Teensy, the code you need is Freescale_Demo_3.ino ...and no, I'm not releasing the earlier 1 and 2 versions.... ;)

Then all you need to do is get "DEMO.BIN" onto your SD card. This part is requires several steps.

First, you run Processing with movie2sdcard.pde. This is similar to movie2serial.pde for live playing, except it writes the data to a file. The filenames and other stuff are hard coded. Pay attention to the frame rate. You MUST edit the Processing code with the exact frame rate. The processing code emits headers into the data with elapsed microseconds, which need to be correct for audio to stay in sync. In other words, if your video is 30 frames/sec, the code will emit 33333, 33333, 33334, 33333, etc, so over the long run those one with 1 extra microsecond cause the overall frame rate to be correct.

Unfortunately, the Processing code plays the video at 1X speed. If anyone knows a way to get processing to just run as fast as possible, please let me know?

The .BIN file from the Processing code can play (if renamed to "DEMO.BIN"), but there's no audio. Adding the audio requires 3 steps.

First, extract the audio from the original video using ffmpeg. For example:

./ffmpeg -i Freescale1.mov -vn -f wav Freescale1.wav

Then use sox to convert from WAV to raw data, and adjust the sample rate. Teensy actually uses 48e6/1088 as its sample rate, which is slightly faster than 44100. Getting it exactly matched will keep your audio in sync. Here's the command:

./sox Freescale1.wav -c 1 -b 16 -r 44117.647 Freescale1.raw

After this, run the "addaudio" command. Source code is below. This reads the original .BIN file from Processing and the .RAW file with the audio and writes a new .BIN file with both streams.

As with everything else, this is an extremely ugly hack (in fact, I wrote all this code within the last 12 hours) with file names and other important stuff hard coded. Hopefully everything you need to edit is near the top of each file. Expect to have to do some fiddling. The addaudio program has only been tested on Mac OSX 10.7. It will probably work on Linux. Windows is less likely to be good.

Once you get the DEMO.BIN from addaudio, just copy it onto the SD card and Freescale_Demo_3.ino ought to be able to play it.
Click to expand...
Hello Paul Stoffregen, thanks for the project Freescale Demo 3.ino I assembled board 88X48 = 4224led i have everything worked out, but there are questions about how to change the brightness? too dark to show the movie. whether it is possible to create one project for 8448 and more from SD Thank look forward to hearing
 
PaulStoffregen said:
Sounds good. Please do put something printed inside the box, with the URL of this thread.

I'll probably end up working with these in mid-June. Quite a bit of stuff has piled up in the last few weeks while I've been focusing on Maker Faire. I also really want to get Teensyduino 1.19 published, with only bug fixes.

Investigating this flicker issue is pretty high on my priority list. This is pretty good timing, since I've now got a lot of spare LEDs and power supplies and other stuff here due to this Maker Faire build.
Click to expand...

Paul, any updates? Did you ever get a chance to look at the example I mailed?

Jim
 
jimparis said:
Paul, any updates? Did you ever get a chance to look at the example I mailed?
Click to expand...

Oh, they've been here. I just located the box again.

I've also got the OctoWS2811 test board set up. I was actually testing OctoWS2811 and Teensy-LC, right when Arduino 1.6.0 came out a couple weeks ago. I just about to get back to OctoWS2811 and DMA stuff, so this is excellent timing. I'll give these a try soon.

I believe I owe you some LEDs and a Teensy. Please email Robin directly (robin@pjrc.com) with your current shipping address.
 
PaulStoffregen said:
Oh, they've been here. I just located the box again.

I've also got the OctoWS2811 test board set up. I was actually testing OctoWS2811 and Teensy-LC, right when Arduino 1.6.0 came out a couple weeks ago. I just about to get back to OctoWS2811 and DMA stuff, so this is excellent timing. I'll give these a try soon.
Click to expand...

Hi Paul,
Just wanted to ping you again and see if you had any thoughts on this (or whether you could see the problem on the strip that I mailed).

Jim
 
You must log in or register to reply here.
Back
Top