PHP基于ffmpeg实现转换视频，截图及生成缩略图的方法

这里把ffmpeg 和  生成缩略图整合了一下：

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=newImageResize();
 $thumbnail->resizeimage("1.jpg", 30,30, 0,"small1.jpg");
classImageResize {
  //图片类型
  var$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;
functionresizeimage($img,$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);
  }
functionnewimg() {
//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,$this->dstimg);
      }
    }
  }
//初始化图象
  functioniniti_img() {
    if($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($this->srcimg);
    }
  }
//图象目标地址
  functiondst_img($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 $this->dstimg;
  }
  functionConvertBMP2GD($src,$dest= false) {
    if(!($src_f=fopen($src,"rb"))) {
      returnfalse;
    }
    if(!($dest_f=fopen($dest,"wb"))) {
      returnfalse;
    }
    $header= unpack("vtype/Vsize/v2reserved/Voffset",fread($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"
      returnfalse;
    }
    $palette_size=$offset- 54;
    $ncolor=$palette_size/ 4;
    $gd_header="";
    // true-color vs. palette
    $gd_header.= ($palette_size== 0) ?"xFFxFE":"xFFxFF";
    $gd_header.= pack("n2",$width,$height);
    $gd_header.= ($palette_size== 0) ?"x01":"x00";
    if($palette_size) {
      $gd_header.= pack("n",$ncolor);
    }
    // no transparency
    $gd_header.="xFFxFFxFFxFF";
fwrite($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";
      }
      $gd_palette.=str_repeat("x00x00x00x00", 256 -$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";
        }
      }
      elseif($bits== 8) {
        $gd_scan_line=$scan_line;
      }
      elseif($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,$width);
      }
      elseif($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($dest_f);
    returntrue;
  }
functionimagecreatefrombmp($filename) {
    $tmp_name= tempnam("/tmp","GD");
    if($this->ConvertBMP2GD($filename,$tmp_name)) {
      $img= imagecreatefromgd($tmp_name);
      unlink($tmp_name);
      return$img;
    }
    returnfalse;
  }
}