PHP uses the GIFEncoder class to generate gif dynamic scrolling captions
- 2021-07-06 10:28:12
- OfStack
Today in the company, the manager asked to do a rolling subtitle. However, gif pictures are not allowed to be generated. So I found GIFEncoder on the Internet. It's really easy to use, but there are also some problems in the application process, which are written here now for later reference and less detours.
Text scrolling can be divided into two situations. The first type is horizontal rolling:
<?php
require_once("GIFEncoder.class.php");
$count=0; // Set default counters
while(true){
$str = $_REQUEST['str'] ? $_REQUEST['str']:" No input at present ";
$length=strlen($str)*9; // Calculate the line length, this calculation is relatively simple, that is, the number of words per word *9 Pixels
$im=imagecreatefromgif("hudongbg.gif"); // Create an image from a picture
$white = ImageColorAllocate($im,255,255,255); // Settings 1 A white
$str = iconv("GB2312","UTF-8",$str); // Special attention is paid to transcoding, because the imagettftext Can only be used utf-8 Code
$now=220-$count*5; // Horizontal position of current operation
imagettftext($im,13,0,$now,20,$white,"ziti.ttf",$str); // Write text on the picture according to the font, parameter meaning (image source, text size, tilt angle, horizontal position, vertical position, color, font file used, content to be written
imagegif($im);
imagedestroy($im);
$imagedata[] = ob_get_contents(); // Create this 1 Image data of frames
ob_clean();
$count++;
if ($now+$length<0){ // If in the end 1 If the text moves to the beginning, it will end
break;
}
}
$diy[]=0;// Start delay time
$gif = new GIFEncoder($imagedata,$diy,0,2,0,0,0,"bin");
ob_start();
Header ('Content-type:image/gif');
echo $gif->GetAnimation();
?>
Then it is vertical:
<?php
/*
From url Obtain "str= No. 1 1 Row ; No. 1 2 Row ; No. 1 3 Row " Data of
*/
require_once("GIFEncoder.class.php");
$array_str=array();
$str=$_GET['str'];
/*
Will $str Convert to an array
*/
if ($str!=''){
$array_str=explode(";",$str);
}else{
$array_str=array(" Welcome to our shop! ");
}
/*
If the array element has no value, clear the last 1 A " ; "
*/
foreach( $array_str as $k=>$v){
if( !$v )
unset( $array_str[$k] );
}
for ($i=0,$length=count($array_str);$i<$length;$i++){
for ($k=0;$k<20;$k++){
$im=imagecreatefromgif("hudongbg.gif"); // Create an image from a picture
$white = ImageColorAllocate($im,255,255,255); // Settings 1 A white
$test = iconv("GB2312","UTF-8",$array_str[$i]); // Special attention is paid to transcoding, because the imagettftext Can only be used utf-8 Coding, attention, 1 Be sure to receive it in a string, not an array, otherwise it will be garbled
$heigth=40-$k; // Current text height
imagettftext($im,13,0,0,$heigth,$white,"ziti.ttf",$test); // Write text to a picture
imagegif($im);
$imagedata[] = ob_get_contents();
ob_clean();
}
}
/*
Here is the setting of every 1 The delay time of the picture, to the first 20 Frame, delay 2 Seconds. Only in this way can words go to the top and pause 1 The effect of the meeting
*/
$delay=array();
for ($i=1,$length=count($array_str)*20;$i<=$length;$i++){
if ($i%20==0){
$delay[$i-1]="200";
}else{
$delay[$i-1]="1";
}
}
$transparent=array(0);
$gif = new GIFEncoder($imagedata,$delay,0,2,0,0,$transparent,"bin");
ob_start();
Header ('Content-type:image/gif');
echo $gif->GetAnimation();
?>
GIFEncoder class source code:
<?php
Class GIFEncoder {
var $GIF = "GIF89a"; /* GIF header 6 bytes */
var $VER = "GIFEncoder V2.06"; /* Encoder version */
var $BUF = Array ( );
var $LOP = 0;
var $DIS = 2;
var $COL = -1;
var $IMG = -1;
var $ERR = Array (
'ERR00' =>"Does not supported function for only one image!",
'ERR01' =>"Source is not a GIF image!",
'ERR02' =>"Unintelligible flag ",
'ERR03' =>"Could not make animation from animated GIF source",
);
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFEncoder...
::
*/
function GIFEncoder (
$GIF_src, $GIF_dly, $GIF_lop, $GIF_dis,
$GIF_red, $GIF_grn, $GIF_blu, $GIF_mod
) {
if ( ! is_array ( $GIF_src ) && ! is_array ( $GIF_tim ) ) {
printf ( "%s: %s", $this->VER, $this->ERR [ 'ERR00' ] );
exit ( 0 );
}
$this->LOP = ( $GIF_lop > -1 ) ? $GIF_lop : 0;
$this->DIS = ( $GIF_dis > -1 ) ? ( ( $GIF_dis < 3 ) ? $GIF_dis : 3 ) : 2;
$this->COL = ( $GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1 ) ?
( $GIF_red | ( $GIF_grn << 8 ) | ( $GIF_blu << 16 ) ) : -1;
for ( $i = 0; $i < count ( $GIF_src ); $i++ ) {
if ( strToLower ( $GIF_mod ) == "url" ) {
$this->BUF [ ] = fread ( fopen ( $GIF_src [ $i ], "rb" ), filesize ( $GIF_src [ $i ] ) );
}
else if ( strToLower ( $GIF_mod ) == "bin" ) {
$this->BUF [ ] = $GIF_src [ $i ];
}
else {
printf ( "%s: %s ( %s )!", $this->VER, $this->ERR [ 'ERR02' ], $GIF_mod );
exit ( 0 );
}
if ( substr ( $this->BUF [ $i ], 0, 6 ) != "GIF87a" && substr ( $this->BUF [ $i ], 0, 6 ) != "GIF89a" ) {
printf ( "%s: %d %s", $this->VER, $i, $this->ERR [ 'ERR01' ] );
exit ( 0 );
}
for ( $j = ( 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) ), $k = TRUE; $k; $j++ ) {
switch ( $this->BUF [ $i ] { $j } ) {
case "!":
if ( ( substr ( $this->BUF [ $i ], ( $j + 3 ), 8 ) ) == "NETSCAPE" ) {
printf ( "%s: %s ( %s source )!", $this->VER, $this->ERR [ 'ERR03' ], ( $i + 1 ) );
exit ( 0 );
}
break;
case ";":
$k = FALSE;
break;
}
}
}
GIFEncoder::GIFAddHeader ( );
for ( $i = 0; $i < count ( $this->BUF ); $i++ ) {
GIFEncoder::GIFAddFrames ( $i, $GIF_dly [ $i ] );
}
GIFEncoder::GIFAddFooter ( );
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFAddHeader...
::
*/
function GIFAddHeader ( ) {
$cmap = 0;
if ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x80 ) {
$cmap = 3 * ( 2 << ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 ) );
$this->GIF .= substr ( $this->BUF [ 0 ], 6, 7 );
$this->GIF .= substr ( $this->BUF [ 0 ], 13, $cmap );
$this->GIF .= "!/377/13NETSCAPE2.0/3/1" . GIFEncoder::GIFWord ( $this->LOP ) . "/0";
}
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFAddFrames...
::
*/
function GIFAddFrames ( $i, $d ) {
$Locals_str = 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) );
$Locals_end = strlen ( $this->BUF [ $i ] ) - $Locals_str - 1;
$Locals_tmp = substr ( $this->BUF [ $i ], $Locals_str, $Locals_end );
$Global_len = 2 << ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 );
$Locals_len = 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );
$Global_rgb = substr ( $this->BUF [ 0 ], 13,
3 * ( 2 << ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 ) ) );
$Locals_rgb = substr ( $this->BUF [ $i ], 13,
3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) );
$Locals_ext = "!/xF9/x04" . chr ( ( $this->DIS << 2 ) + 0 ) .
chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . "/x0/x0";
if ( $this->COL > -1 && ord ( $this->BUF [ $i ] { 10 } ) & 0x80 ) {
for ( $j = 0; $j < ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ); $j++ ) {
if (
ord ( $Locals_rgb { 3 * $j + 0 } ) == ( $this->COL >> 0 ) & 0xFF &
ord ( $Locals_rgb { 3 * $j + 1 } ) == ( $this->COL >> 8 ) & 0xFF &
ord ( $Locals_rgb { 3 * $j + 2 } ) == ( $this->COL >> 16 ) & 0xFF
) {
$Locals_ext = "!/xF9/x04" . chr ( ( $this->DIS << 2 ) + 1 ) .
chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . chr ( $j ) . "/x0";
break;
}
}
}
switch ( $Locals_tmp { 0 } ) {
case "!":
$Locals_img = substr ( $Locals_tmp, 8, 10 );
$Locals_tmp = substr ( $Locals_tmp, 18, strlen ( $Locals_tmp ) - 18 );
break;
case ",":
$Locals_img = substr ( $Locals_tmp, 0, 10 );
$Locals_tmp = substr ( $Locals_tmp, 10, strlen ( $Locals_tmp ) - 10 );
break;
}
if ( ord ( $this->BUF [ $i ] { 10 } ) & 0x80 && $this->IMG > -1 ) {
if ( $Global_len == $Locals_len ) {
if ( GIFEncoder::GIFBlockCompare ( $Global_rgb, $Locals_rgb, $Global_len ) ) {
$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
}
else {
$byte = ord ( $Locals_img { 9 } );
$byte |= 0x80;
$byte &= 0xF8;
$byte |= ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 );
$Locals_img { 9 } = chr ( $byte );
$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
}
}
else {
$byte = ord ( $Locals_img { 9 } );
$byte |= 0x80;
$byte &= 0xF8;
$byte |= ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );
$Locals_img { 9 } = chr ( $byte );
$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
}
}
else {
$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
}
$this->IMG = 1;
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFAddFooter...
::
*/
function GIFAddFooter ( ) {
$this->GIF .= ";";
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFBlockCompare...
::
*/
function GIFBlockCompare ( $GlobalBlock, $LocalBlock, $Len ) {
for ( $i = 0; $i < $Len; $i++ ) {
if (
$GlobalBlock { 3 * $i + 0 } != $LocalBlock { 3 * $i + 0 } ||
$GlobalBlock { 3 * $i + 1 } != $LocalBlock { 3 * $i + 1 } ||
$GlobalBlock { 3 * $i + 2 } != $LocalBlock { 3 * $i + 2 }
) {
return ( 0 );
}
}
return ( 1 );
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFWord...
::
*/
function GIFWord ( $int ) {
return ( chr ( $int & 0xFF ) . chr ( ( $int >> 8 ) & 0xFF ) );
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GetAnimation...
::
*/
function GetAnimation ( ) {
return ( $this->GIF );
}
}
?>