}

// Read presents one or more IDAT chunks as one continuous stream (minus the
// intermediate chunk headers and footers). If the PNG data looked like:
//
//	... len0 IDAT xxx crc0 len1 IDAT yy crc1 len2 IEND crc2
//
// then this reader presents xxxyy. For well-formed PNG data, the decoder state
// immediately before the first Read call is that d.r is positioned between the

		e.tmp[3*256+i] = c1.A
	}
	e.writeChunk(e.tmp[:3*len(p)], "PLTE")
	if last != -1 {
		e.writeChunk(e.tmp[3*256:3*256+1+last], "tRNS")
	}
}

// An encoder is an io.Writer that satisfies writes by writing PNG IDAT chunks,
// including an 8-byte header and 4-byte CRC checksum per Write call. Such calls
// should be relatively infrequent, since writeIDATs uses a [bufio.Writer].
//