PHP基于ffmpeg实现转换视频，截图及生成缩略图的方法

　　本文实例讲述了PHP基于ffmpeg实现转换视频，截图及生成缩略图的方法。分享给大家供大家参考，具体如下：

　　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 = 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; } }

　　附：完整实例代码点击此处本站下载。

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　　希望本文所述对大家PHP程序设计有所帮助。