github.com/phpdave11/gofpdf@v1.4.2/contrib/tiff/tiff.go (about)

     1  /*
     2   * Copyright (c) 2016 Kurt Jung (Gmail: kurt.w.jung)
     3   *
     4   * Permission to use, copy, modify, and distribute this software for any
     5   * purpose with or without fee is hereby granted, provided that the above
     6   * copyright notice and this permission notice appear in all copies.
     7   *
     8   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
     9   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
    10   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    11   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    12   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
    13   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    14   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
    15   */
    16  
    17  // Package tiff allows standard (LZW-compressed) TIFF images to be used in
    18  // documents generated with gofpdf.
    19  package tiff
    20  
    21  import (
    22  	"bytes"
    23  	"fmt"
    24  	"image"
    25  	"image/png"
    26  	"io"
    27  	"os"
    28  
    29  	"github.com/phpdave11/gofpdf"
    30  	"golang.org/x/image/tiff"
    31  )
    32  
    33  // RegisterReader registers a TIFF image, adding it to the PDF file but not
    34  // adding it to the page. imgName specifies the name that will be used in the
    35  // call to Image() that actually places the image in the document. options
    36  // specifies various image properties; in this case, the ImageType property
    37  // should be set to "tiff". The TIFF image is a reader from the reader
    38  // specified by r.
    39  func RegisterReader(fpdf *gofpdf.Fpdf, imgName string, options gofpdf.ImageOptions, r io.Reader) (info *gofpdf.ImageInfoType) {
    40  	var err error
    41  	var img image.Image
    42  	var buf bytes.Buffer
    43  	if fpdf.Ok() {
    44  		if options.ImageType == "tiff" || options.ImageType == "tif" {
    45  			img, err = tiff.Decode(r)
    46  			if err == nil {
    47  				err = png.Encode(&buf, img)
    48  				if err == nil {
    49  					options.ImageType = "png"
    50  					info = fpdf.RegisterImageOptionsReader(imgName, options, &buf)
    51  				}
    52  			}
    53  		} else {
    54  			err = fmt.Errorf("expecting \"tiff\" or \"tif\" as image type, got \"%s\"", options.ImageType)
    55  		}
    56  		if err != nil {
    57  			fpdf.SetError(err)
    58  		}
    59  	}
    60  	return
    61  }
    62  
    63  // RegisterFile registers a TIFF image, adding it to the PDF file but not
    64  // adding it to the page. imgName specifies the name that will be used in the
    65  // call to Image() that actually places the image in the document. options
    66  // specifies various image properties; in this case, the ImageType property
    67  // should be set to "tiff". The TIFF image is read from the file specified by
    68  // tiffFileStr.
    69  func RegisterFile(fpdf *gofpdf.Fpdf, imgName string, options gofpdf.ImageOptions, tiffFileStr string) (info *gofpdf.ImageInfoType) {
    70  	var f *os.File
    71  	var err error
    72  
    73  	if fpdf.Ok() {
    74  		f, err = os.Open(tiffFileStr)
    75  		if err == nil {
    76  			info = RegisterReader(fpdf, imgName, options, f)
    77  			f.Close()
    78  		} else {
    79  			fpdf.SetError(err)
    80  		}
    81  	}
    82  	return
    83  }