reduce pixel width for fast scan lines

app/src/main/java/xdsopl/robot36/Decoder.java

@@ -66,7 +66,7 @@ public class Decoder {
 		double scanLineToleranceSeconds = 0.001;
 		scanLineToleranceSamples = (int) Math.round(scanLineToleranceSeconds * sampleRate);
 		scanLineReserveSamples = sampleRate;
-		rawMode = new RawDecoder();
+		rawMode = new RawDecoder(sampleRate);
 		lastMode = rawMode;
 		lastScanLineSamples = (int) Math.round(0.150 * sampleRate);
 		syncPulse5msModes = new ArrayList<>();

app/src/main/java/xdsopl/robot36/RawDecoder.java

@@ -8,8 +8,12 @@ package xdsopl.robot36;
 
 public class RawDecoder implements Mode {
 	private final ExponentialMovingAverage lowPassFilter;
+	private final int smallPictureMaxSamples;
+	private final int mediumPictureMaxSamples;
 
-	RawDecoder() {
+	RawDecoder(int sampleRate) {
+		smallPictureMaxSamples = (int) Math.round(0.125 * sampleRate);
+		mediumPictureMaxSamples = (int) Math.round(0.175 * sampleRate);
 		lowPassFilter = new ExponentialMovingAverage();
 	}
 
@@ -32,6 +36,10 @@ public class RawDecoder implements Mode {
 		if (syncPulseIndex < 0 || syncPulseIndex + scanLineSamples > scanLineBuffer.length)
 			return false;
 		int horizontalPixels = pixelBuffer.width;
+		if (scanLineSamples < smallPictureMaxSamples)
+			horizontalPixels /= 2;
+		if (scanLineSamples < mediumPictureMaxSamples)
+			horizontalPixels /= 2;
 		lowPassFilter.cutoff(horizontalPixels, 2 * scanLineSamples, 2);
 		lowPassFilter.reset();
 		for (int i = 0; i < scanLineSamples; ++i)
@@ -43,6 +51,7 @@ public class RawDecoder implements Mode {
 			int position = (i * scanLineSamples) / horizontalPixels;
 			pixelBuffer.pixels[i] = ColorConverter.GRAY(scratchBuffer[position]);
 		}
+		pixelBuffer.width = horizontalPixels;
 		pixelBuffer.height = 1;
 		return true;
 	}