PHP基于ffmpeg实现转换视频，截图及生成缩略图的方法

include("ImageResize.class.php") //转视频 $cmd="ffmpeg.exe -i starwar.avi -ab 56 -ar 22050 -b 500 -r 15 -s 320x240 1.flv"; exec($cmd); //视频截图 $cmd="ffmpeg.exe -i starwar.avi -f image2 -ss 10 -s 400*300 -vframes 1 1.jpg"; exec($cmd); //生成缩略图 $thumbnail = new ImageResize(); $thumbnail->resizeimage("1.jpg", 30,30, 0, "small1.jpg");class ImageResize {  //图片类型  var $type;  //实际宽度  var $width;  //实际高度  var $height;  //改变后的宽度  var $resize_width;  //改变后的高度  var $resize_height;  //是否裁图  var $cut;  //源图象  var $srcimg;  //目标图象地址  var $dstimg;  //临时创建的图象  var $im;function resizeimage($img, $wid, $hei,$c,$dstpath) {    $this->srcimg = $img;    $this->resize_width = $wid;    $this->resize_height = $hei;    $this->cut = $c;    //图片的类型    $this->type = strtolower(substr(strrchr($this->srcimg,"."),1));    //初始化图象    $this->initi_img();    //目标图象地址    $this -> dst_img($dstpath);    //--    $this->width = imagesx($this->im);    $this->height = imagesy($this->im);    //生成图象    $this->newimg();    ImageDestroy ($this->im);  }function newimg() {//改变后的图象的比例    $resize_ratio = ($this->resize_width)/($this->resize_height);//实际图象的比例    $ratio = ($this->width)/($this->height);if(($this->cut)=="1") {      //裁图 高度优先      if($ratio>=$resize_ratio){        $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);        imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width,$this->resize_height, (($this->height)*$resize_ratio), $this->height);        ImageJpeg ($newimg,$this->dstimg);      }      //裁图 宽度优先      if($ratio<$resize_ratio) {        $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);        imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, $this->resize_height, $this->width, (($this->width)/$resize_ratio));        ImageJpeg ($newimg,$this->dstimg);      }    } else {      //不裁图      if($ratio>=$resize_ratio) {        $newimg = imagecreatetruecolor($this->resize_width,($this->resize_width)/$ratio);        imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, ($this->resize_width)/$ratio, $this->width, $this->height);        ImageJpeg ($newimg,$this->dstimg);      }      if($ratio<$resize_ratio) {        $newimg = imagecreatetruecolor(($this->resize_height)*$ratio,$this->resize_height);        imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, ($this->resize_height)*$ratio, $this->resize_height, $this->width, $this->height);        ImageJpeg ($newimg,$this->dstimg);      }    }  }//初始化图象  function initi_img() {    if($this->type=="jpg") {      $this->im = imagecreatefromjpeg($this->srcimg);    }    if($this->type=="gif") {      $this->im = imagecreatefromgif($this->srcimg);    }    if($this->type=="png") {      $this->im = imagecreatefrompng($this->srcimg);    }    if($this->type=="bmp") {      $this->im = $this->imagecreatefrombmp($this->srcimg);    }  }//图象目标地址  function dst_img($dstpath) {    $full_length = strlen($this->srcimg);    $type_length = strlen($this->type);    $name_length = $full_length-$type_length;    $name = substr($this->srcimg,0,$name_length-1);    $this->dstimg = $dstpath;    //echo $this->dstimg;  }  function ConvertBMP2GD($src, $dest = false) {    if(!($src_f = fopen($src, "rb"))) {      return false;    }    if(!($dest_f = fopen($dest, "wb"))) {      return false;    }    $header = unpack("vtype/Vsize/v2reserved/Voffset", fread($src_f,14));    $info = unpack("Vsize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vncolor/Vimportant", fread($src_f, 40));    extract($info);    extract($header);    if($type != 0x4D42) { // signature "BM"      return false;    }    $palette_size = $offset - 54;    $ncolor = $palette_size / 4;    $gd_header = "";    // true-color vs. palette    $gd_header .= ($palette_size == 0) ? "/xFF/xFE" : "/xFF/xFF";    $gd_header .= pack("n2", $width, $height);    $gd_header .= ($palette_size == 0) ? "/x01" : "/x00";    if($palette_size) {      $gd_header .= pack("n", $ncolor);    }    // no transparency    $gd_header .= "/xFF/xFF/xFF/xFF";fwrite($dest_f, $gd_header);if($palette_size) {      $palette = fread($src_f, $palette_size);      $gd_palette = "";      $j = 0;      while($j < $palette_size) {        $b = $palette{$j++};        $g = $palette{$j++};        $r = $palette{$j++};        $a = $palette{$j++};        $gd_palette .= "$r$g$b$a";      }      $gd_palette .= str_repeat("/x00/x00/x00/x00", 256 - $ncolor);      fwrite($dest_f, $gd_palette);    }$scan_line_size = (($bits * $width) + 7) >> 3;    $scan_line_align = ($scan_line_size & 0x03) ? 4 - ($scan_line_size &    0x03) : 0;for($i = 0, $l = $height - 1; $i < $height; $i++, $l--) {      // BMP stores scan lines starting from bottom      fseek($src_f, $offset + (($scan_line_size + $scan_line_align) * $l));      $scan_line = fread($src_f, $scan_line_size);      if($bits == 24) {        $gd_scan_line = "";        $j = 0;        while($j < $scan_line_size) {          $b = $scan_line{$j++};          $g = $scan_line{$j++};          $r = $scan_line{$j++};          $gd_scan_line .= "/x00$r$g$b";        }      }      else if($bits == 8) {        $gd_scan_line = $scan_line;      }      else if($bits == 4) {        $gd_scan_line = "";        $j = 0;        while($j < $scan_line_size) {          $byte = ord($scan_line{$j++});          $p1 = chr($byte >> 4);          $p2 = chr($byte & 0x0F);          $gd_scan_line .= "$p1$p2";        }        $gd_scan_line = substr($gd_scan_line, 0, $width);      }      else if($bits == 1) {        $gd_scan_line = "";        $j = 0;        while($j < $scan_line_size) {          $byte = ord($scan_line{$j++});          $p1 = chr((int) (($byte & 0x80) != 0));          $p2 = chr((int) (($byte & 0x40) != 0));          $p3 = chr((int) (($byte & 0x20) != 0));          $p4 = chr((int) (($byte & 0x10) != 0));          $p5 = chr((int) (($byte & 0x08) != 0));          $p6 = chr((int) (($byte & 0x04) != 0));          $p7 = chr((int) (($byte & 0x02) != 0));          $p8 = chr((int) (($byte & 0x01) != 0));          $gd_scan_line .= "$p1$p2$p3$p4$p5$p6$p7$p8";        }        $gd_scan_line = substr($gd_scan_line, 0, $width);      }      fwrite($dest_f, $gd_scan_line);    }    fclose($src_f);    fclose($dest_f);    return true;  }function imagecreatefrombmp($filename) {    $tmp_name = tempnam("/tmp", "GD");    if($this->ConvertBMP2GD($filename, $tmp_name)) {      $img = imagecreatefromgd($tmp_name);      unlink($tmp_name);      return $img;    }    return false;  }}