Screenshot

[graaaeme10]

Hi there, I've been scouring the internet and forum for a solution to this, but I haven't found anything yet.
I'm trying to take a screenshot and retrieve with python, as shown in some examples.

Here's the arduino code:

#include <EEPROM.h>

#include <SPI.h>

#include <GD2.h>



////////////////////////////////////////////////////////////////////////

#define REG_SCREENSHOT_EN    (ft8xx_model ? 0x302010UL : 0x102410UL) // Set to enable screenshot mode

#define REG_SCREENSHOT_Y     (ft8xx_model ? 0x302014UL : 0x102414UL) // Y line register

#define REG_SCREENSHOT_START (ft8xx_model ? 0x302018UL : 0x102418UL) // Screenshot start trigger

#define REG_SCREENSHOT_BUSY  (ft8xx_model ? 0x3020e8UL : 0x1024d8UL) // Screenshot ready flags

#define REG_SCREENSHOT_READ  (ft8xx_model ? 0x302174UL : 0x102554UL) // Set to enable readout

#define RAM_SCREENSHOT       (ft8xx_model ? 0x3c2000UL : 0x1C2000UL) // Screenshot readout buffer



////////////////////////////////////////////////////////////////////////







void screenshot_480x272() {

   int x, y;

   GD.wr(REG_SCREENSHOT_EN, 1);

   Serial.write("P6\n480\n272\n255\n");  // PPM header

   for (y = 0; y < 272; y++) {

       GD.wr16(REG_SCREENSHOT_Y, y);

       GD.wr(REG_SCREENSHOT_START, 1);

       while (GD.rd32(REG_SCREENSHOT_BUSY) | GD.rd32(REG_SCREENSHOT_BUSY + 4));

       GD.wr(REG_SCREENSHOT_READ, 1);

       for (x = 0; x < 480; x++) {

           char rgb[3];

           unsigned char b = GD.rd(RAM_SCREENSHOT + (4 * x) + 0);

           unsigned char g = GD.rd(RAM_SCREENSHOT + (4 * x) + 1);

           unsigned char r = GD.rd(RAM_SCREENSHOT + (4 * x) + 2);

           unsigned char a = GD.rd(RAM_SCREENSHOT + (4 * x) + 3);

           Serial.write(r);

           Serial.write(g);

           Serial.write(b);

       }

       GD.wr(REG_SCREENSHOT_READ, 0);

   }

   GD.wr16(REG_SCREENSHOT_EN, 0);

}







void setup()

{

 Serial.begin(115200);

 GD.begin();

}



void loop()

{

 GD.cmd_gradient(0, 0, 0x000000, 480, 272, 0x303080);

 GD.Begin(POINTS);

 for (int i = 0; i < 100; i++) {

   GD.ColorRGB(GD.random(256), GD.random(256), GD.random(256));

   GD.PointSize(GD.random(200));

   GD.Vertex2ii(GD.random(480), GD.random(272));

 }

 GD.ColorRGB(0xffffff);

 GD.cmd_text(240, 136, 31, OPT_CENTER, "This is a screenshot");

 GD.swap();



 delay(5000);   // 6 second delay, time to start serial capture

 screenshot_480x272();

}
And the python script:

import sys

import time



import serial



if __name__ == '__main__':

   import sys, getopt

   try:

       optlist, args = getopt.getopt(sys.argv[1:], "vh:s:")



   except getopt.GetoptError, reason:

       print reason

       print

       print 'usage: getppm.py -h <usb port> -s <usb speed>'

       print

       print

       sys.exit(1)

   optdict = dict(optlist)



   if '-s' in optdict:

       speed = int(optdict['-s'])

   else:

       speed = 115200



   port = optdict.get('-h', "COM3")

   print 'Opening %s at %d' % (port, speed)

   ser = serial.Serial(port, speed)



   ser.setDTR(0)

   time.sleep(0.1)

   ser.setDTR(1)



   # Expected size of the PPM. 15 bytes for the header, then 480x272 image

   expected_size = 15 + (3 * 480 * 272)

   for frame in xrange(1):

       # z = ser.read_until('0x400806b8')

       # print z

       # print 'From here -----'

       s = ser.read(expected_size)

       print s

       open("shot%04d.ppm" % frame, "w").write(s)

       print "frame %d written" % frame



After a bit of fiddling I managed to get a .ppm output, which unfortunately appears corrupted when opened in irfanview:



I am on windows 10, using python 2.7 to run the script.
Arduino Uno, gameduino 3x

Any ideas to solve this problem?
Thanks

[jamesbowman]

I think it is *almost* working!

I think this line, opening the output file:

open("shot%04d.ppm" % frame, "w").write(s)
should be:


open("shot%04d.ppm" % frame, "wb").write(s)
because the file contains binary data.

This might improve things.

[graaaeme10]

Worked! Thank you!