who could help me ,

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1

who could help me , on the look who we can use live video grabbing and showing on a led matrix off 1024 Apa 102 led .
A bit like face candy but with the open source off Fastled library .
any one has a idea …

2

Your biggest issue is likely to be getting the data from the computer to the MCU.

1024 APA 102 leds is likely to not be a problem for FastLED (however, I have not yet verified that the 12Mhz data rate is sustainable for 1024 leds - I have a panel w/784 apa102 leds on order, but I don’t know when that will arrive). Memory is also not going to be an issue.

So, it’s just a question of pushing data over USB to the teensy 3.1. Look at the OctoWS2811 examples for VideoDisplay to see a processing application and .ino file for receiving frame data and a rough idea for how to do it. Note that the example there is pre-doing a bunch of bit-rotation that OctoWS2811 needs that you would not need or want to use for your application.

But basically, your ino file is going to look like:

CRGB leds[NUM_LEDS];
uint8_t frameStart[4] = { 0xDE, 0xAD, 0xBE, 0xEF };

void setup() {
LEDS.addLeds(leds, NUM_LEDS);
// setup serial (is this necessary on the teensy 3.1?)
Serial.begin(57600);
}

void waitForStartFrame() {
bool frameStart = false;
uint8_t i = 0;
while(i < 4) {
uint8_t c = Serial.read();
if(c == frameStart[i++]) { continue; }
if(c == frameStart[0]) { i = 1; continue; }
i = 0;
}
}

void readFrameOfData(CRGB leds, int nLedsToRead) {
// wait for a start of frame sequence
waitForStartFrame();
if(Serial.readBytes(leds,nLedsToReadsizeof(CRGB)) == (nLedsToRead*3)) {
// we got a full frame!
}

void loop() {
// wait for a start of frame
waitForStartFrame();
if(Serial.readBytes(leds,NUM_LEDS3) == NUM_LEDS3) {
LEDS.show();
}
}

this is just a rough outline, of course.

3

Thanks , I had some basic idea in processing with a frame grabber .

It will tray in the morning … Buth processing is not my strongest point .

4

Coming late to the party, but glediator http://www.solderlab.de/index.php/software/glediator and jinx! http://www.live-leds.de/ can do this, I know glediator can send data to usb, there is an arduino sketch linked to Fastled for that.

5

thansk , i used jinx with succes …