alpha support

Author: cr3ative

example_bins/image_btn_balance_fader_centre_icon_0_ovg.bin

@@ -10,9 +10,9 @@
 # Describes command block and RLE routine
 
 # variables; adjust me
-filename = "example_bins/mex_ovg.bin"
-width = 39
-height = 39
+filename = "example_bins/ops_ovg.bin"
+width = 172
+# height automatically calculated
 
 # First, deal with RLE compression as defined by the NXP PDF above
 
@@ -61,8 +61,26 @@
         # Read next command block
         cmd = file.read(1)
 
+totalPixels = int(len(bytesOut) / 4)
+print(f"Image data contains {totalPixels} pixels")
+height = int(totalPixels / width)
+print(f"Calculated as {width}x{height}")
+
 # Cast RGBX byte stream to image using Pillow
-image = Image.frombytes('RGB', (width, height), bytes(bytesOut), 'raw', 'RGBX')
-output = "logo.png"
+image = Image.frombytes('RGBA', (width, height), bytes(bytesOut), 'raw', 'RGBA')
+
+output = "ovg.png"
 image.save(output)
 print(output + ' saved')
+
+# Enable the block below to do fast image size discovery; tweak the range
+# Open the image in an auto refreshing viewer and hit enter until it looks coherent
+if (True):
+
+    for autoWidth in range(440, 500, 1):
+        # Generate at given width
+        autoHeight = int(totalPixels / autoWidth)
+        image = Image.frombytes('RGBA', (autoWidth, autoHeight), bytes(bytesOut), 'raw', 'RGBA')
+        output = "ovg.png"
+        image.save(output)
+        input(f"Saved at {autoWidth} x {autoHeight} - press enter to continue...")

example_bins/img_btn_tuner_main_preset_01_a_bg_ovg.bin

@@ -20,6 +20,8 @@
 chksumGreen = functools.reduce(operator.xor, np.array([g]).transpose().flatten())
 # and red
 chksumRed = functools.reduce(operator.xor, np.array([r]).transpose().flatten())
+# and alpha
+chksumAlpha = functools.reduce(operator.xor, np.array([a]).transpose().flatten())
 
 # img output
 data = np.array([b, g, r, a])
@@ -29,12 +31,11 @@
 f = open('./output.bin', 'wb')
 # B G R A ordered data
 f.write(bgrArray)
-# pixel colour checksums
+# pixel checksums
 f.write(chksumBlue)
 f.write(chksumGreen)
 f.write(chksumRed)
-# 1 byte of empty padding
-f.write(bytes(1))
+f.write(chksumAlpha)
 f.close()
 
 print('output.bin saved')

example_bins/img_car_ops_sk251_0in_k_ovg.bin

@@ -11,7 +11,7 @@
 # let's go!
 in_file = open(filename, "rb")  # opening for [r]eading as [b]inary
 data = in_file.read() 
-img = Image.frombytes('RGB', (width, height), data, 'raw', 'BGRX')
+img = Image.frombytes('RGBA', (width, height), data, 'raw', 'BGRA')
 output = "logo.png"
 img.save(output)
 print(output + ' saved')