switch name {
				case "IHDR":
					bitdepth := data[i+8+8]
					if bitdepth != tc.bitdepth {
						t.Errorf("got bitdepth %d, want %d", bitdepth, tc.bitdepth)
					}
				case "IDAT":
					// Uncompress the image data
					r, err := zlib.NewReader(bytes.NewReader(data[i+8 : i+8+int(length)]))
					if err != nil {
						t.Error(err)
						return
					}
					n, err := io.Copy(io.Discard, r)