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不用GD库生成当前时间的PNG格式图象的程序

时间:2021-07-01 10:21:17 帮助过:37人阅读

该程序是不用GD库可以生成当前时间的PNG格式图象,给人大开眼界,很有参考价值. teaman整理

   
  function set_4pixel($r, $g, $b, $x, $y)
  {
  global $sx, $sy, $pixels;

  $ofs = 3 * ($sx * $y + $x);
  $pixels[$ofs] = chr($r);
  $pixels[$ofs + 1] = chr($g);
  $pixels[$ofs + 2] = chr($b);
  $pixels[$ofs + 3] = chr($r);
  $pixels[$ofs + 4] = chr($g);
  $pixels[$ofs + 5] = chr($b);
  $ofs += 3 * $sx;
  $pixels[$ofs] = chr($r);
  $pixels[$ofs + 1] = chr($g);
  $pixels[$ofs + 2] = chr($b);
  $pixels[$ofs + 3] = chr($r);
  $pixels[$ofs + 4] = chr($g);
  $pixels[$ofs + 5] = chr($b);
  }
  //生成数字图象的函数  
  function draw2digits($x, $y, $number)
  {
  draw_digit($x, $y, (int) ($number / 10));
  draw_digit($x + 11, $y, $number % 10);
  }
    
  function draw_digit($x, $y, $digit)
  {
  global $sx, $sy, $pixels, $digits, $lines;
      
  $digit = $digits[$digit];
  $m = 8;
  for ($b = 1, $i = 0; $i < 7; $i++, $b *= 2) {
    if (($b & $digit) == $b) {
    $j = $i * 4;
    $x0 = $lines[$j] * $m + $x;
    $y0 = $lines[$j + 1] * $m + $y;
    $x1 = $lines[$j + 2] * $m + $x;
    $y1 = $lines[$j + 3] * $m + $y;
    if ($x0 == $x1) {
      $ofs = 3 * ($sx * $y0 + $x0);
      for ($h = $y0; $h <= $y1; $h++, $ofs += 3 * $sx) {
      $pixels[$ofs] = chr(0);
      $pixels[$ofs + 1] = chr(0);
      $pixels[$ofs + 2] = chr(0);
      }
    } else {
      $ofs = 3 * ($sx * $y0 + $x0);
      for ($w = $x0; $w <= $x1; $w++) {
      $pixels[$ofs++] = chr(0);
      $pixels[$ofs++] = chr(0);
      $pixels[$ofs++] = chr(0);
      }
    }
    }
  }
  }
    
  //将文字加入到图象中
  function add_chunk($type)
  {
  global $result, $data, $chunk, $crc_table;

  // chunk :为层
  // length: 4 字节: 用来计算 chunk
  // chunk type: 4 字节
  // chunk data: length bytes
  // CRC: 4 字节: 循环冗余码校验
    
  // copy data and create CRC checksum
  $len = strlen($data);
  $chunk = pack("c*", ($len >> 24) & 255,
    ($len >> 16) & 255,
    ($len >> 8) & 255,
    $len & 255);
  $chunk .= $type;
  $chunk .= $data;

  // calculate a CRC checksum with the bytes chunk[4..len-1]
  $z = 16777215;
  $z |= 255 << 24;
  $c = $z;
  for ($n = 4; $n < strlen($chunk); $n++) {
    $c8 = ($c >> 8) & 0xffffff;
    $c = $crc_table[($c ^ ord($chunk][$n])) & 0xff] ^ $c8;
  }
  $crc = $c ^ $z;

  $chunk .= chr(($crc >> 24) & 255);
  $chunk .= chr(($crc >> 16) & 255);
  $chunk .= chr(($crc >> 8) & 255);
  $chunk .= chr($crc & 255);

  // 将结果加到$result中
  $result .= $chunk;
  }


  //主程序

  $sx = 80;
  $sy = 21;
  $pixels = "";
      
  // 填充
  for ($h = 0; $h < $sy; $h++) {
  for ($w = 0; $w < $sx; $w++) {
    $r = 100 / $sx * $w + 155;
    $g = 100 / $sy * $h + 155;
    $b = 255 - (100 / ($sx + $sy) * ($w + $h));
    $pixels .= chr($r);
    $pixels .= chr($g);
    $pixels .= chr($b);
  }
  }
    
  $date = getdate();
  $s = $date["seconds"];
  $m = $date["minutes"];
  $h = $date["hours"];
  $digits = array(95, 5, 118, 117, 45, 121, 123, 69, 127, 125);
  $lines = array(1, 1, 1, 2, 0, 1, 0, 2, 1, 0, 1, 1, 0, 0, 0, 1, 0, 2, 1, 2, 0, 1, 1, 1, 0, 0, 1, 0);
    
  draw2digits(4, 2, $h);
  draw2digits(30, 2, $m);
  draw2digits(56, 2, $s);
  set_4pixel(0, 0, 0, 26, 7);
  set_4pixel(0, 0, 0, 26, 13);
  set_4pixel(0, 0, 0, 52, 7);
  set_4pixel(0, 0, 0, 52, 13);

  // 创建循环冗余码校验表
  $z = -306674912; // = 0xedb88320
  for ($n = 0; $n < 256; $n++) {
    $c = $n;
    for ($k = 0; $k < 8; $k++) {
      $c2 = ($c >> 1) & 0x7fffffff;
      if ($c & 1) $c = $z ^ ($c2); else $c = $c2;
    }
    $crc_table[$n] = $c;
  }

  // PNG file signature
  $result = pack("c*", 137,80,78,71,13,10,26,10);
    
  // IHDR chunk data:
  //  width:       4 bytes
  //  height:       4 bytes
  //  bit depth:     1 byte (8 bits per RGB value)
  //  color type:     1 byte (2 = RGB)
  //  comPRession method: 1 byte (0 = deflate/inflate)
  //  filter method:   1 byte (0 = adaptive filtering)
  //  interlace method:  1 byte (0 = no interlace)
  $data = pack("c*", ($sx >> 24) & 255,
  ($sx >> 16) & 255,
  ($sx >> 8) & 255,
  $sx & 255,
  ($sy >> 24) & 255,
  ($sy >> 16) & 255,
  ($sy >> 8) & 255,
  $sy & 255,
  8,
  2,
  0,
  0,
  0);
  add_chunk("IHDR");

  // 以下不敢乱翻译,请自行参考
  //  scanline:
  //    filter byte: 0 = none
  //    RGB bytes for the line
  //  the scanline is compressed with "zlib", method 8 (RFC-1950):
  //    compression method/flags code: 1 byte ($78 = method 8, 32k window)
  //    additional flags/check bits:  1 byte ($01: FCHECK = 1, FDICT = 0, FLEVEL = 0)
  //    compressed data blocks:    n bytes
  //      one block (RFC-1951):
  //        bit 0: BFINAL: 1 for the last block
  //        bit 1 and 2: BTYPE: 0 for no compression
  //        next 2 bytes: LEN (LSB first)
  //        next 2 bytes: one's complement of LEN
  //        LEN bytes uncompressed data
  //    check value: 4 bytes (Adler-32 checksum of the uncompressed data)
  //
  $len = ($sx * 3 + 1) * $sy;
  $data = pack("c*", 0x78, 0x01,
    1,
  $len & 255,
  ($len >> 8) & 255,
  255 - ($len & 255),
  255 - (($len >> 8) & 255));
  $start = strlen($data);
  $i2 = 0;
  for ($h = 0; $h < $sy; $h++) {
  $data .= chr(0);
  for ($w = 0; $w < $sx * 3; $w++) {
    $data .= $pixels[$i2++];
  }
  }


  // calculate a Adler32 checksum with the bytes data[start..len-1]
  $s1 = 1;
  $s2 = 0;
  for ($n = $start; $n < strlen($data); $n++) {
  $s1 = ($s1 + ord($data[$n])) % 65521;
  $s2 = ($s2 + $s1) % 65521;
  }
  $adler = ($s2 << 16) | $s1;

  $data .= chr(($adler >> 24) & 255);
  $data .= chr(($adler >> 16) & 255);
  $data .= chr(($adler >> 8) & 255);
  $data .= chr($adler & 255);
  add_chunk("IDAT");

  // IEND: marks the end of the PNG-file
  $data = "";
  add_chunk("IEND");

  // 列印图象
  
  echo($result);
?>

//如何调用,其实很简单,将上面存为https://www.gxlcms.com/Timeimg.php
//然后新建一个页面如下:


 
  test
 
 
 
  //以图象连接方式调用PHP文件

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