static int expand_rle_row(const uint8_t *in_buf, const uint8_t* in_end,
            unsigned char *out_buf, uint8_t* out_end, int pixelstride)
{
    unsigned char pixel, count;
    unsigned char *orig = out_buf;

    while (1) {
        if(in_buf + 1 > in_end) return -1;
        pixel = bytestream_get_byte(&in_buf);
        if (!(count = (pixel & 0x7f))) {
            return (out_buf - orig) / pixelstride;
        }

        /* Check for buffer overflow. */
        if(out_buf + pixelstride * count >= out_end) return -1;

        if (pixel & 0x80) {
            while (count--) {
                *out_buf = bytestream_get_byte(&in_buf);
                out_buf += pixelstride;
            }
        } else {
            pixel = bytestream_get_byte(&in_buf);

            while (count--) {
                *out_buf = pixel;
                out_buf += pixelstride;
            }
        }
    }
}