@Override
	public String toString() {
		StringBuffer buff = new StringBuffer();

		buff.append("Data Length: " + length + "\n");
		buff.append("Chunk ID: " + new String(chunkID) + "\n");
		buff.append("Width: " + imgWidth + "\n");
		buff.append("Height: " + imgHeight + "\n");
		buff.append("Bit Depth: " + bitDepth + "\n");
		buff.append("Color Type: " + colorType + "\n");
		buff.append("Compression Method: " + compressionMethod + "\n");
		buff.append("Filter Method: " + filterMethod + "\n");
		buff.append("Interlace Method: " + interlaceMethod + "\n");
		buff.append("Bits Per Palette: " + bitsPerPalette + "\n");
		buff.append("Bytes Per Line: " + (imgWidth * bitsPerPalette + 7) / 8 + "\n");
		buff.append("CRC32: " + crc32 + "\n");

		return buff.toString();
	}
<pre>
	   From PNG Specs, http://www.w3.org/TR/PNG-Chunks.html
	   Color    Allowed    Interpretation
	   Type    Bit Depths
	   ------  ----------  ----------------------------------
	   0       1,2,4,8,16  Each pixel is a grayscale sample.
	   
	   2       8,16        Each pixel is an R,G,B triple.
	   
	   3       1,2,4,8     Each pixel is a palette index;
	                       a PLTE chunk must appear.
	   
	   4       8,16        Each pixel is a grayscale sample,
	                       followed by an alpha sample.
	   
	   6       8,16        Each pixel is an R,G,B triple,
	                       followed by an alpha sample.
</pre>
Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/png/IHDRChunk.java