Generate a PDF page thumbnail on iOS

To create a PDF page thumbnail in multiple image formats.

Obj-C

PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: filename];

// set the output resolution
PTPDFDraw *draw = [[PTPDFDraw alloc] initWithDpi: 92];

// Rasterize the first page in the document and save the result as PNG.
PTPage* pg = [doc GetPage: 1];
[draw Export:pg filename: output_filename format: @"PNG"];

Swift

let doc: PTPDFDoc = PTPDFDoc(filepath: filename)

// The output resolution is set to 92 DPI
let draw: PTPDFDraw = PTPDFDraw(dpi: 92)

// Rasterize the first page in the document and save the result as PNG.
let pg: PTPage = doc.getPage(1)
draw.export(pg, filename: output_filename, format: "PNG")

Convert PDF to image (JPG, PNG, BMP, TIFF) Full code sample illustrates how to use the built-in rasterizer in order to render PDF images on the fly and how to save resulting images in PNG and JPEG format.

More image format options:

• "RAW" : RAW format.There are four possibilities:

  • e_rgba - if transparent and color page;
  • e_gray_alpha - if transparent and gray page;
  • e_rgb - if opaque and color page;
  • e_gray - if opaque and gray page. NOTE that if page is set to be transparent (SetPageTransparent), the output color channels are already multiplied by the alpha channel.
• "BMP" : Bitmap image format (BMP)
• "JPEG" : Joint Photographic Experts Group (JPEG) image format
• "PNG" : 24-bit W3C Portable Network Graphics (PNG) image format
• "PNG8" : 8-bit, palettized PNG format. The exported file size should be smaller than the one generated using "PNG", possibly at the expense of some image quality.
• "TIFF" : Tag Image File Format (TIFF) image format.
• "TIFF8" : Tag Image File Format (TIFF) image format (with 8-bit palete).