Prototyping raw image sequence assignment (2013)

Assignment: In Python, following the techniques shown in the Raw image and Raw image sequence examples, create a 1 second long animation by generating 25 frames of an image sequence and converting them to a GIF. Use just the basics: loops, variables, and if statements.

Rules:

The code should be "pure" python (just using the standard libraries of python such as struct).
The code should be no more than 50 lines.
The images should be 320 x 240 pixels in size.

Results

To be posted / linked to here. Please post both your code (again, PURE python -- no libraries and less than 50 lines) + the resulting image (converted to GIF and uploaded to the wiki).

Luisa

import struct, sys

width = 320
height = 240
header = struct.pack("<BBBHHBHHHHBB",0,0,2,0,0,8,0,0,width,height,32,1<<5)

totalframes = 25

for frame in xrange(totalframes):
    out = open("frame%04d.tga" % frame, "wb")
    out.write(header)
    for y in xrange(height):
        for x in xrange(width):
            r = (1.0-(float(frame)/totalframes))*255
            g = 0
            b = 0
            a = 255
            if y < 32 and y > 100:
                a = 35
                b = 125
            if x > 80 and x < 160:
                g = r
            out.write(struct.pack('B', b))
            out.write(struct.pack('B', g))
            out.write(struct.pack('B', r))
            out.write(struct.pack('B', a))
print r
out.close()

Lucia

import struct, sys
 
width = 320
height = 240
xWhite = 0
header = struct.pack("<BBBHHBHHHHBB",0,0,2,0,0,8,0,0,width,height,32,1<<5)

 
totalframes = 25
for frame in xrange(totalframes):
    frame = frame+1
    out = open("frames/frame%02d.tga" % frame, "wb")
    out.write(header)
 
    for y in xrange(height):
        for x in xrange(width):
            xWhite = xWhite +1
            if (frame != 1 and xWhite%frame == 0):
                r = 255
                g = 255
                b = 255
                a = 255
            else:
                r = 0
                g = 0
                b = 0
                a = 255
            out.write(struct.pack('B', b))
            out.write(struct.pack('B', g))
            out.write(struct.pack('B', r))
            out.write(struct.pack('B', a))
 
    out.close()

A variation (that's actually the original idea - the previous code was 'accidental'):

import struct, sys
 
width = 320
height = 240
header = struct.pack("<BBBHHBHHHHBB",0,0,2,0,0,8,0,0,width,height,32,1<<5)

 
totalframes = 25
for frame in xrange(totalframes):
    out = open("last/frame_%02d.tga" % frame, "wb")
    out.write(header)
 
    for y in xrange(height):
        for x in xrange(width):
            #if (x%10==0 and x == frame*10):
            #line above is redundant either one condition or the other would be enough, so
            if ( x == frame*10):
                r = 255
                g = 255
                b = 255
                a = 255
            else:
                r = 0
                g = 0
                b = 0
                a = 255
            out.write(struct.pack('B', b))
            out.write(struct.pack('B', g))
            out.write(struct.pack('B', r))
            out.write(struct.pack('B', a))
 
    out.close()

Tamas

import math, struct, sys
from math import *
tau = 2 * pi

#computes distance from (x1,y1) to (x2,y2)
def dist(x1, y1, x2, y2):
    return sqrt(float((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2)))

width = 320
height = 240
nFrames = 25
header = struct.pack("<BBBHHBHHHHBB",0,0,2,0,0,8,0,0,width,height,32,1<<5)

for frame in xrange(nFrames):
    output = open("frames/frame%02d.tga" % frame, "wb")
    output.write(header)
 
    for y in xrange(height):
        for x in xrange(width):
            offset = frame * (1.0 / nFrames)
            primaryColor = abs(sin((0.2)*tau + (x) / (4.0+8.0*sin((0.2)*pi)))
                + cos((0.2)*tau + (x+y) / (6.0+16.0*cos((0.2)*tau)))
                + sin(dist(x, y, 32*sin(offset*tau)+96, 32*cos(offset*tau)+height / 2) / 24.0) # orbit 1 on left side 
                + sin(dist(x, y, 32*cos(offset*tau) + width-96, 32*sin(offset*tau)+height / 2) / 8.0) # orbit 2 on right side
                )
            r = abs(primaryColor - abs(cos(dist(x + sin(offset*tau), y + 25*sin(offset*tau), width / 2, -2000) / 4.0))) * 48
            g = primaryColor * 48 if primaryColor >= 2 else primaryColor * 36 if primaryColor > 0.2 else abs(cos(5.0*dist(x + sin(offset*tau), y + 25*sin(offset*tau), width / 2, -2000) / 4.0)) * 24
            b = abs(primaryColor + abs(cos(2000*offset*tau + dist(x + sin(offset*tau), y + sin(offset*tau), width / 2, -2000) / 8.0))) * 48
            a = 255

            output.write(struct.pack('BBBB', b, g, r, a))

    output.close()