Scale to fit and centre-align an image with FPDF

gistfile1.php

<?php
/* Caveat: I'm not a PHP programmer, so this may or may
 * not be the most idiomatic code...
 *
 * FPDF is a free PHP library for creating PDFs:
 * http://www.fpdf.org/
 */
require("fpdf.php");

class PDF extends FPDF {

    const DPI = 96;
    const MM_IN_INCH = 25.4;
    const A4_HEIGHT = 297;
    const A4_WIDTH = 210;
    // tweak these values (in pixels)
    const MAX_WIDTH = 800;
    const MAX_HEIGHT = 500;

    function pixelsToMM($val) {
        return $val * self::MM_IN_INCH / self::DPI;
    }

    function resizeToFit($imgFilename) {
        list($width, $height) = getimagesize($imgFilename);

        $widthScale = self::MAX_WIDTH / $width;
        $heightScale = self::MAX_HEIGHT / $height;

        $scale = min($widthScale, $heightScale);

        return array(
            round($this->pixelsToMM($scale * $width)),
            round($this->pixelsToMM($scale * $height))
        );
    }

    function centreImage($img) {
        list($width, $height) = $this->resizeToFit($img);

        // you will probably want to swap the width/height
        // around depending on the page's orientation
        $this->Image(
            $img, (self::A4_HEIGHT - $width) / 2,
            (self::A4_WIDTH - $height) / 2,
            $width,
            $height
        );
    }
}

// usage:
$pdf = new PDF();
$pdf->AddPage("L");
$pdf->centreImage("path/to/my/image.jpg");
$pdf->Output();

?>

This is not scale-able in the least bit. Constants for file images?

<?php
require("fpdf.php");

class Pdf extends \FPDF
{

    const DPI = 300;
    const MM_IN_INCH = 25.4;
    const A4_HEIGHT = 297;
    const A4_WIDTH = 210;

     /**
     * Resize et fit une image image
     *
     * @param string $imgPath
     * @param integer $x
     * @param integer $y
     * @param integer $containerWidth
     * @param integer $containerHeight
     * @param string $alignment
     * @return void
     */
    public function imageUniformToFill(string $imgPath, int $x = 0, int $y = 0, int $containerWidth = 210, int $containerHeight = 297, string $alignment = 'C')
    {
        list($width, $height) = $this->resizeToFit($imgPath, $containerWidth, $containerHeight);

        if ($alignment === 'R')
        {
            $this->Image($imgPath, $x+$containerWidth-$width, $y+($containerHeight-$height)/2, $width, $height);
        }
        else if ($alignment === 'B')
        {
            $this->Image($imgPath, $x, $y+$containerHeight-$height, $width, $height);
        }
        else if ($alignment === 'C')
        {
            $this->Image($imgPath, $x+($containerWidth-$width)/2, $y+($containerHeight-$height)/2, $width, $height);
        }
        else
        {
            $this->Image($imgPath, $x, $y, $width, $height);
        }
    }
    
    /**
     * Convertit des pixels en mm
     *
     * @param integer $val
     * @return integer
     */
    protected function pixelsToMm(int $val) : int
    {
        return (int)(round($val * $this::MM_IN_INCH / $this::DPI));
    }

    /**
     * Convertit des mm en pixels
     *
     * @param integer $val
     * @return integer
     */
    protected function mmToPixels(int $val) : int
    {
        return (int)(round($this::DPI * $val / $this::MM_IN_INCH));
    }

    /**
     * Resize une image
     *
     * @param string $imgPath
     * @param integer $maxWidth en mm
     * @param integer $maxHeight en mm
     * @return int[]
     */
    protected function resizeToFit(string $imgPath, int $maxWidth = 210, int $maxHeight = 297) : array
    {
        list($width, $height) = getimagesize($imgPath);
        $widthScale = $this->mmtopixels($maxWidth) / $width;
        $heightScale = $this->mmToPixels($maxHeight) / $height;
        $scale = min($widthScale, $heightScale);
        return array(
            $this->pixelsToMM($scale * $width),
            $this->pixelsToMM($scale * $height)
        );
    }
}

// usage:
$pdf = new Pdf();
$pdf->AddPage();
$pdf->imageUniformToFill($imgPath, $x, $y ,$containerWidth, $containerHeight, $alignment) //$alignment "B", "T", "L", "R", "C"
$pdf->Output();

Merci à https://gist.github.com/benshimmin/4088493
https://gist.github.com/thomasdesmoulin/398886164ffd0566f6fa3b3171bb86f4

Amazing! Thank you so much!

Thank you so much for this!!! I'm finding this kind of solution for weeks now. Really made my day. Thank you

Thank you benshimmin and other contributors, great job !

Thanks a lot! Its works, but just one detail... if the image has a small width, with a long height, the image overflows from the top and bottom of the PDF sheet.

Thankyou thomasdesmoulin its works for me