ios - I have inserted an image into pdf digital signature layer n2 using mupdf, but it not showed up -

i using mupdf(git clone @ commit 2014/3/5 4:05) sign pdf.

, i've succeeded sign digital signature in pdf function 'pdf_sign_signature'.

i'm trying insert image layer n2 of signature when i'm signing it.

there's function called 'pdf_set_signature_appearance' in '/source/pdf/pdf-appearance.c'.

try add codes below insert image:

image_doc = (image_document *)fz_open_document(ctx, jpgfilepathandname); fz_fill_image(dev, image_doc->image, page_ctm, 1.0f); 

these codes inserted between:

rect = annot->rect; rect.x0 = (rect.x0 + rect.x1)/2.0f; text = fit_text(ctx, &font_rec, (char *)bufstr, &rect); fz_fill_text(dev, text, page_ctm, cs, font_rec.da_rec.col, 1.0f); 

and

rect = annot->rect; fz_transform_rect(&rect, page_ctm); pdf_set_annot_appearance(doc, annot, &rect, dlist); 

after executing, got pdf file this:

%pdf-1.4 %μῦ  1 0 obj <<   /type /font   /basefont /helvetica   /subtype /type1   /encoding /winansiencoding >> endobj  2 0 obj <<   /length 63 >> stream q bt 36 806 td 0 -18 td /f1 12 tf (hello world!)tj 0 0 td et q endstream endobj  3 0 obj <<   /count 1   /type /pages   /itxt (5.3.0)   /kids [ 4 0 r ] >> endobj  4 0 obj <<   /annots 10 0 r   /contents 2 0 r   /mediabox [ 0 0 595 842 ]   /parent 3 0 r   /resources <<     /font <<       /f1 1 0 r     >>     /procset [ /pdf /text /imageb /imagec /imagei ]   >>   /type /page >> endobj  5 0 obj <<   /acroform 8 0 r   /metadata 9 0 r   /pages 3 0 r   /type /catalog >> endobj  6 0 obj <<   /creationdate (d:20120620091727+02'00')   /moddate (d:20120804153425+02'00')   /producer (itext\256 5.3.0 \2512000-2012 1t3xt bvba) >> endobj  7 0 obj <<   /ap <<     /n 17 0 r   >>   /da (/helv 0 tf 0 g)   /f 4   /ft /sig   /mk <<   >>   /p 4 0 r   /rect [ 41.3670998 713.710022 237.352997 781.257996 ]   /subtype /widget   /t (signature1)   /type /annot   /v 15 0 r >> endobj  8 0 obj <<   /da (/helv 0 tf 0 g )   /dr <<     /encoding <<       /pdfdocencoding 14 0 r     >>     /font <<       /helv 12 0 r       /zadb 13 0 r     >>     /xobject <<       /dsz 11 0 r     >>   >>   /fields [ 7 0 r ]   /sigflags 1 >> endobj  9 0 obj <<   /length 3304   /subtype /xml   /type /metadata >> stream <?xpacket begin="" id="w5m0mpcehihzreszntczkc9d"?> <x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="adobe xmp core 4.2.1-c043 52.372728, 2009/01/18-15:08:04        ">    <rdf:rdf xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">       <rdf:description rdf:about=""             xmlns:xmp="http://ns.adobe.com/xap/1.0/">          <xmp:createdate>2012-06-20t09:17:27+02:00</xmp:createdate>          <xmp:modifydate>2012-08-04t15:34:25+02:00</xmp:modifydate>          <xmp:metadatadate>2012-08-04t15:34:25+02:00</xmp:metadatadate>       </rdf:description>       <rdf:description rdf:about=""             xmlns:pdf="http://ns.adobe.com/pdf/1.3/">          <pdf:producer>itext® 5.3.0 ©2000-2012 1t3xt bvba</pdf:producer>       </rdf:description>       <rdf:description rdf:about=""             xmlns:dc="http://purl.org/dc/elements/1.1/">          <dc:format>application/pdf</dc:format>       </rdf:description>       <rdf:description rdf:about=""             xmlns:xmpmm="http://ns.adobe.com/xap/1.0/mm/">          <xmpmm:documentid>uuid:547fb234-f327-4f3d-8dd1-7b7ea87df336</xmpmm:documentid>          <xmpmm:instanceid>uuid:72437fbf-7b45-4062-98f1-2b53d3ad86d0</xmpmm:instanceid>       </rdf:description>    </rdf:rdf> </x:xmpmeta>                      <?xpacket end="w"?>endstream endobj  10 0 obj [ 7 0 r ] endobj  11 0 obj <<   /bbox [ 41.3670998 713.710022 237.352997 781.257996 ]   /length 67   /resources <<     /xobject <<       /img0 16 0 r     >>   >>   /subtype /form   /type /xobject   /matrix [ 1 0 0 1 0 0 ] >> stream 1.000000 0.000000 0.000000 -1.000000 0.000000 1.000000 cm /img0 endstream endobj  12 0 obj <<   /basefont /helvetica   /encoding 14 0 r   /name /helv   /subtype /type1   /type /font >> endobj  13 0 obj <<   /basefont /zapfdingbats   /name /zadb   /subtype /type1   /type /font >> endobj  14 0 obj <<   /differences [ 24 /breve /caron /circumflex /dotaccent /hungarumlaut      /ogonek /ring /tilde 39 /quotesingle 96 /grave 128 /bullet      /dagger /daggerdbl /ellipsis /emdash /endash /florin /fraction      /guilsinglleft /guilsinglright /minus /perthousand /quotedblbase      /quotedblleft /quotedblright /quoteleft /quoteright /quotesinglbase      /trademark /fi /fl /lslash /oe /scaron /ydieresis /zcaron      /dotlessi /lslash /oe /scaron /zcaron 160 /euro 164 /currency      166 /brokenbar 168 /dieresis /copyright /ordfeminine 172      /logicalnot /.notdef /registered /macron /degree /plusminus      /twosuperior /threesuperior /acute /mu 183 /periodcentered      /cedilla /onesuperior /ordmasculine 188 /onequarter /onehalf      /threequarters 192 /agrave /aacute /acircumflex /atilde /adieresis      /aring /ae /ccedilla /egrave /eacute /ecircumflex /edieresis      /igrave /iacute /icircumflex /idieresis /eth /ntilde /ograve      /oacute /ocircumflex /otilde /odieresis /multiply /oslash      /ugrave /uacute /ucircumflex /udieresis /yacute /thorn /germandbls      /agrave /aacute /acircumflex /atilde /adieresis /aring /ae      /ccedilla /egrave /eacute /ecircumflex /edieresis /igrave      /iacute /icircumflex /idieresis /eth /ntilde /ograve /oacute      /ocircumflex /otilde /odieresis /divide /oslash /ugrave /uacute      /ucircumflex /udieresis /yacute /thorn /ydieresis ]   /type /encoding >> endobj  15 0 obj <<   /byterange[0 6712 10814 12756]                               /contents  ...   /filter /adobe.ppklite   /subfilter /adbe.pkcs7.detached >> endobj  16 0 obj <<   /type /xobject   /subtype /image   /width 400   /height 332   /colorspace /devicergb   /bitspercomponent 8   /length 11097 >> stream ... endstream endobj  17 0 obj <<   /bbox [ 41.3670998 713.710022 237.352997 781.257996 ]   /formtype 1   /length 7   /matrix [ 1 0 0 1 0 0 ]   /resources <<     /procset [ /pdf /text ]     /xobject <<       /frm 18 0 r     >>   >>   /subtype /form   /type /xobject >> stream /frm doendstream endobj  18 0 obj <<   /bbox [ 41.3670998 713.710022 237.352997 781.257996 ]   /formtype 1   /length 51   /matrix [ 1 0 0 1 0 0 ]   /resources <<     /procset [ /pdf /text ]     /xobject <<       /n0 19 0 r       /n2 11 0 r     >>   >>   /subtype /form   /type /xobject >> stream q 1 0 0 1 0 0 cm /n0 q q 1 0 0 1 0 0 cm /n2 qendstream endobj  19 0 obj <<   /bbox [ 41.3670998 713.710022 237.352997 781.257996 ]   /formtype 1   /length 9   /matrix [ 1 0 0 1 0 0 ]   /resources <<     /procset [ /pdf /text ]   >>   /subtype /form   /type /xobject >> stream % dsblankendstream endobj  xref 0 20 0000000000 65536 f  0000000017 00000 n  0000000123 00000 n  0000000238 00000 n  0000000320 00000 n  0000000544 00000 n  0000000634 00000 n  0000000790 00000 n  0000001026 00000 n  0000001272 00000 n  0000004664 00000 n  0000004691 00000 n  0000004990 00000 n  0000005101 00000 n  0000005196 00000 n  0000006628 00000 n  0000010882 00000 n  0000022144 00000 n  0000022423 00000 n  0000022763 00000 n   trailer <<   /size 20   /info 6 0 r   /root 5 0 r   /id [ <d0151a7adf2410cf3e72a04b9cb83452> <fa2030fcc5a66742887f23e51dec5875> ] >>  startxref 23003 %%eof 

it seems correct, since there's /n2 11 0 r in 18 0 obj , /img0 16 0 r in 11 0 obj , 16 0 obj looks well-formed image xobject.

image doesn't show when using pdf reader open pdf.

please give me clue what's wrong pdf file, , how insert image correctly.

lot.

ps.
signed_with_image_only.pdf

signed_with_text_and_image.pdf

signed_with_image_only.pdf pdf i've added '\n' before 'endstream'. can see image doesn't show in form below 'hello world!'.

signed_with_text_and_image.pdf pretty same signed_with_image_only.pdf, put text in layer n2 show text insertion ok. same image inserted, , not showed up.

the transformation matrix not right.

you can use other pdf utility, pdfbox, add image digital signature appearance, analyze transformation matrix on image painting, pay attention on bbox.