moved implementation classes to separate modules

color.py

@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+from __future__ import division
+from sstv import FREQ_BLACK, FREQ_RANGE, FREQ_SYNC
+from grayscale import GrayscaleSSTV
+
+class ColorSSTV(GrayscaleSSTV):
+	RED, GREEN, BLUE = range(3)
+
+	def encode_line(self, line):
+		cs = self.COLOR_SEQ
+		msec_pixel = self.SCAN / self.WIDTH
+		image = self.image
+		for index in cs:
+			for item in self.before_channel(index):
+				yield item
+			for col in xrange(self.WIDTH):
+				pixel = image.getpixel((col, line))
+				value = pixel[index]
+				freq_pixel = FREQ_BLACK + FREQ_RANGE * value / 255
+				yield freq_pixel, msec_pixel
+
+	def before_channel(self, index):
+		return []
+
+
+class MartinM1(ColorSSTV):
+	COLOR_SEQ = (ColorSSTV.GREEN, ColorSSTV.BLUE, ColorSSTV.RED)
+	VIS_CODE = 0x2c
+	WIDTH = 320
+	HEIGHT = 256
+	SYNC = 4.862
+	SCAN = 146.432
+	INTER_CH_GAP = 0.572
+
+	def before_channel(self, index):
+		if index != ColorSSTV.GREEN:
+			yield FREQ_BLACK, self.INTER_CH_GAP
+
+
+class MartinM2(MartinM1):
+	VIS_CODE = 0x28
+	WIDTH = 160
+	SCAN = 73.216
+
+
+class ScottieS1(MartinM1):
+	VIS_CODE = 0x3c
+	SYNC = 9
+	SCAN = 138.24
+	INTER_CH_GAP = 1.5
+
+	def horizontal_sync(self):
+		return []
+
+	def before_channel(self, index):
+		if index != ColorSSTV.RED:
+			yield FREQ_SYNC, self.SYNC
+		yield FREQ_BLACK, self.INTER_CH_GAP
+
+
+class ScottieS2(ScottieS1):
+	VIS_CODE = 0x38
+	SCAN = 88.064
+	WIDTH = 160

grayscale.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+
+from __future__ import division
+from sstv import FREQ_BLACK, FREQ_RANGE, FREQ_SYNC, SSTV
+
+class GrayscaleSSTV(SSTV):
+	def gen_freq_bits(self):
+		for item in SSTV.gen_freq_bits(self):
+			yield item
+		for line in xrange(self.HEIGHT):
+			for item in self.horizontal_sync():
+				yield item
+			for item in self.encode_line(line):
+				yield item
+
+	def horizontal_sync(self):
+		yield FREQ_SYNC, self.SYNC
+
+	def encode_line(self, line):
+		msec_pixel = self.SCAN / self.WIDTH
+		image = self.image
+		for col in xrange(self.WIDTH):
+			pixel = image.getpixel((col, line))
+			value = sum(pixel) / len(pixel)
+			freq_pixel = FREQ_BLACK + FREQ_RANGE * value / 255
+			yield freq_pixel, msec_pixel
+
+
+class Robot8BW(GrayscaleSSTV):
+	VIS_CODE = 0x02
+	WIDTH = 160
+	HEIGHT = 120
+	SYNC = 10
+	SCAN = 56
+
+
+class Robot24BW(GrayscaleSSTV):
+	VIS_CODE = 0x0A
+	WIDTH = 320
+	HEIGHT = 240
+	SYNC = 12
+	SCAN = 93

sstv.py

@@ -84,108 +84,9 @@ class SSTV(object):
 		yield FREQ_SYNC, MSEC_VIS_BIT # stop bit
 
 
-class GrayscaleSSTV(SSTV):
-	def gen_freq_bits(self):
-		for item in SSTV.gen_freq_bits(self):
-			yield item
-		for line in xrange(self.HEIGHT):
-			for item in self.horizontal_sync():
-				yield item
-			for item in self.encode_line(line):
-				yield item
-
-	def horizontal_sync(self):
-		yield FREQ_SYNC, self.SYNC
-
-	def encode_line(self, line):
-		msec_pixel = self.SCAN / self.WIDTH
-		image = self.image
-		for col in xrange(self.WIDTH):
-			pixel = image.getpixel((col, line))
-			value = sum(pixel) / len(pixel)
-			freq_pixel = FREQ_BLACK + FREQ_RANGE * value / 255
-			yield freq_pixel, msec_pixel
-
-
-class ColorSSTV(GrayscaleSSTV):
-	RED, GREEN, BLUE = range(3)
-
-	def encode_line(self, line):
-		cs = self.COLOR_SEQ
-		msec_pixel = self.SCAN / self.WIDTH
-		image = self.image
-		for index in cs:
-			for item in self.before_channel(index):
-				yield item
-			for col in xrange(self.WIDTH):
-				pixel = image.getpixel((col, line))
-				value = pixel[index]
-				freq_pixel = FREQ_BLACK + FREQ_RANGE * value / 255
-				yield freq_pixel, msec_pixel
-
-	def before_channel(self, index):
-		return []
-
-
-class Robot8BW(GrayscaleSSTV):
-	VIS_CODE = 0x02
-	WIDTH = 160
-	HEIGHT = 120
-	SYNC = 10
-	SCAN = 56
-
-
-class Robot24BW(GrayscaleSSTV):
-	VIS_CODE = 0x0A
-	WIDTH = 320
-	HEIGHT = 240
-	SYNC = 12
-	SCAN = 93
-
-
-class MartinM1(ColorSSTV):
-	COLOR_SEQ = (ColorSSTV.GREEN, ColorSSTV.BLUE, ColorSSTV.RED)
-	VIS_CODE = 0x2c
-	WIDTH = 320
-	HEIGHT = 256
-	SYNC = 4.862
-	SCAN = 146.432
-	INTER_CH_GAP = 0.572
-
-	def before_channel(self, index):
-		if index != ColorSSTV.GREEN:
-			yield FREQ_BLACK, self.INTER_CH_GAP
-
-
-class MartinM2(MartinM1):
-	VIS_CODE = 0x28
-	WIDTH = 160
-	SCAN = 73.216
-
-
-class ScottieS1(MartinM1):
-	VIS_CODE = 0x3c
-	SYNC = 9
-	SCAN = 138.24
-	INTER_CH_GAP = 1.5
-
-	def horizontal_sync(self):
-		return []
-
-	def before_channel(self, index):
-		if index != ColorSSTV.RED:
-			yield FREQ_SYNC, self.SYNC
-		yield FREQ_BLACK, self.INTER_CH_GAP
-
-
-class ScottieS2(ScottieS1):
-	VIS_CODE = 0x38
-	SCAN = 88.064
-	WIDTH = 160
-
-
 if __name__ == '__main__':
 	from PIL import Image
+	from grayscale import Robot8BW
 	image = Image.open('160x120bw.png')
 	s = Robot8BW(image, 48000, 16)
 	s.write_wav('test.wav')