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Fix EPS protocol violations in PostscriptQRCode: remove showpage and setpagedevice from EPS output #694

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Merged
Shane32 merged 6 commits into from
Mar 27, 2026
Merged

Fix EPS protocol violations in PostscriptQRCode: remove showpage and setpagedevice from EPS output #694

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696ad94
Fix EPS protocol violations in PostscriptQRCode: remove showpage and …
Shane32 Mar 26, 2026
dc92dd1
Update TransposeVerificationTests postscript approval file for EPS/PS…
Shane32 Mar 26, 2026
5b7ca44
Improve EPS DSC compliance: use standard prolog/setup sections and fi…
Shane32 Mar 26, 2026
a520e93
Use private dictionary in EPS prolog to prevent name collisions in ho…
Shane32 Mar 26, 2026
ab32b8c
Remove %%Origin from EPS header (not applicable to EPS files)
Shane32 Mar 26, 2026
306d3b4
Fix EPS private dictionary size from 5 to 7 (includes sz and sc)
Shane32 Mar 26, 2026
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107 changes: 91 additions & 16 deletions QRCoder/PostscriptQRCode.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -101,20 +101,24 @@ public string GetGraphic(Size viewBox, Color darkColor, Color lightColor, bool d
var drawableModulesCount = QrCodeData.ModuleMatrix.Count - (drawQuietZones ? 0 : offset * 2);
var pointsPerModule = (double)Math.Min(viewBox.Width, viewBox.Height) / (double)drawableModulesCount;

var estimatedCapacity = PS_HEADER.Length + PS_FUNCTIONS.Length + PS_FOOTER.Length +
var header = epsFormat ? EPS_HEADER : PS_HEADER;
var functions = epsFormat ? EPS_FUNCTIONS : PS_FUNCTIONS;
var footer = epsFormat ? EPS_FOOTER : PS_FOOTER;

var estimatedCapacity = header.Length + functions.Length + footer.Length +
(drawableModulesCount * drawableModulesCount * 2) + // modules (either "f " or "b ")
drawableModulesCount * 3 + // newlines ("nl\n")
200; // embedded numbers
var sb = new StringBuilder(estimatedCapacity);

sb.AppendFormat(CultureInfo.InvariantCulture, PS_HEADER, [
CleanSvgVal(viewBox.Width), CleanSvgVal(pointsPerModule),
epsFormat ? "EPSF-3.0" : string.Empty
sb.AppendFormat(CultureInfo.InvariantCulture, header, [
CleanSvgVal(viewBox.Width), CleanSvgVal(pointsPerModule)
]);
sb.AppendFormat(CultureInfo.InvariantCulture, PS_FUNCTIONS, [
sb.AppendFormat(CultureInfo.InvariantCulture, functions, [
CleanSvgVal(darkColor.R /255.0), CleanSvgVal(darkColor.G /255.0), CleanSvgVal(darkColor.B /255.0),
CleanSvgVal(lightColor.R /255.0), CleanSvgVal(lightColor.G /255.0), CleanSvgVal(lightColor.B /255.0),
drawableModulesCount
drawableModulesCount,
CleanSvgVal(viewBox.Width), CleanSvgVal(pointsPerModule)
]);

for (int xi = offset; xi < offset + drawableModulesCount; xi++)
Expand All @@ -127,7 +131,7 @@ public string GetGraphic(Size viewBox, Color darkColor, Color lightColor, bool d
}
}
sb.Append('\n');
sb.Append(PS_FOOTER);
sb.Append(footer);
return sb.ToString();
}

Expand All @@ -140,15 +144,17 @@ public string GetGraphic(Size viewBox, Color darkColor, Color lightColor, bool d

// Note: line terminations here will encode differently based on which platform QRCoder was compiled on (CRLF vs LF);
// however, PostScript interpreters should handle both equally well.

// Standard PostScript header — includes media/page setup and setpagedevice (valid for standalone PS documents).
private const string PS_HEADER = """
%!PS-Adobe-3.0 {2}
%!PS-Adobe-3.0
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%Origin: 0
%%DocumentMedia: Default {0} {0} 0 () ()
%%BoundingBox: 0 0 {0} {0}
%%LanguageLevel: 2
%%LanguageLevel: 2
%%Pages: 1
%%Page: 1 1
%%EndComments
Expand All @@ -162,8 +168,22 @@ public string GetGraphic(Size viewBox, Color darkColor, Color lightColor, bool d

""";

// EPS header — omits %%DocumentMedia, %%Pages, %%Page, and setpagedevice, all of which are
// forbidden or inappropriate in Encapsulated PostScript (Adobe Technical Note #5002).
// Constants (sz, sc) and procedure definitions are emitted in EPS_FUNCTIONS below.
private const string EPS_HEADER = """
%!PS-Adobe-3.0 EPSF-3.0
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%BoundingBox: 0 0 {0} {0}
%%LanguageLevel: 2
%%EndComments

""";

private const string PS_FUNCTIONS = """
%%BeginFunctions
%%BeginFunctions
/csquare {{
newpath
0 0 moveto
Expand All @@ -174,15 +194,15 @@ 1 0 rlineto
setrgbcolor
fill
}} def
/f {{
/f {{
{0} {1} {2} csquare
1 0 translate
}} def
/b {{
/b {{
1 0 translate
}} def
/background {{
{3} {4} {5} csquare
}} def
/background {{
{3} {4} {5} csquare
}} def
/nl {{
-{6} -1 translate
Expand All @@ -200,10 +220,65 @@ sc sc scale

""";

// EPS variant: uses standard DSC %%BeginProlog/%%EndProlog for procedure definitions,
// %%BeginSetup/%%EndSetup for constants, and moves 0 0 moveto inside gsave so it does
// not leak the current point into the surrounding document.
private const string EPS_FUNCTIONS = """
%%BeginProlog
7 dict begin
/csquare {{
newpath
0 0 moveto
0 1 rlineto
1 0 rlineto
0 -1 rlineto
closepath
setrgbcolor
fill
}} def
/f {{
{0} {1} {2} csquare
1 0 translate
}} def
/b {{
1 0 translate
}} def
/background {{
{3} {4} {5} csquare
}} def
/nl {{
-{6} -1 translate
}} def
%%EndProlog
%%BeginSetup
/sz {7} def
/sc {8} def
%%EndSetup
gsave
0 0 moveto
sz sz scale
background
grestore
gsave
sc sc scale
0 {6} 1 sub translate

""";

// Standard PostScript footer — showpage is required for standalone PS documents.
private const string PS_FOOTER = """
%%EndBody
grestore
showpage
showpage
%%EOF

""";

// EPS footer — showpage is forbidden in EPS files (Adobe Technical Note #5002).
// 'end' pops the private dictionary pushed in %%BeginProlog to avoid polluting the host dict stack.
private const string EPS_FOOTER = """
grestore
end
%%EOF

""";
Expand Down
18 changes: 9 additions & 9 deletions QRCoderTests/PostscriptQRCodeRendererTests.can_render_postscript_qrcode_colors.approved.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,11 +1,11 @@
%!PS-Adobe-3.0
%!PS-Adobe-3.0
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%Origin: 0
%%DocumentMedia: Default 165 165 0 () ()
%%BoundingBox: 0 0 165 165
%%LanguageLevel: 2
%%LanguageLevel: 2
%%Pages: 1
%%Page: 1 1
%%EndComments
Expand All @@ -16,7 +16,7 @@
%%BeginFeature: *PageSize Default
<< /PageSize [ sz sz ] /ImagingBBox null >> setpagedevice
%%EndFeature
%%BeginFunctions
%%BeginFunctions
/csquare {
newpath
0 0 moveto
Expand All @@ -27,15 +27,15 @@
setrgbcolor
fill
} def
/f {
/f {
1 0 0 csquare
1 0 translate
} def
/b {
/b {
1 0 translate
} def
/background {
0 0 1 csquare
} def
/background {
0 0 1 csquare
} def
/nl {
-33 -1 translate
Expand Down Expand Up @@ -85,5 +85,5 @@ b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b
%%EndBody
grestore
showpage
showpage
%%EOF
38 changes: 15 additions & 23 deletions QRCoderTests/PostscriptQRCodeRendererTests.can_render_postscript_qrcode_eps.approved.txt
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -2,21 +2,11 @@
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%Origin: 0
%%DocumentMedia: Default 165 165 0 () ()
%%BoundingBox: 0 0 165 165
%%LanguageLevel: 2
%%Pages: 1
%%Page: 1 1
%%LanguageLevel: 2
%%EndComments
%%BeginConstants
/sz 165 def
/sc 5 def
%%EndConstants
%%BeginFeature: *PageSize Default
<< /PageSize [ sz sz ] /ImagingBBox null >> setpagedevice
%%EndFeature
%%BeginFunctions
%%BeginProlog
7 dict begin
/csquare {
newpath
0 0 moveto
Expand All @@ -27,23 +17,26 @@
setrgbcolor
fill
} def
/f {
/f {
0 0 0 csquare
1 0 translate
} def
/b {
/b {
1 0 translate
} def
/background {
1 1 1 csquare
} def
/background {
1 1 1 csquare
} def
/nl {
-33 -1 translate
} def
%%EndFunctions
%%BeginBody
0 0 moveto
%%EndProlog
%%BeginSetup
/sz 165 def
/sc 5 def
%%EndSetup
gsave
0 0 moveto
sz sz scale
background
grestore
Expand Down Expand Up @@ -83,7 +76,6 @@ b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b
%%EndBody
grestore
showpage
end
%%EOF
18 changes: 9 additions & 9 deletions QRCoderTests/PostscriptQRCodeRendererTests.can_render_postscript_qrcode_simple.approved.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,11 +1,11 @@
%!PS-Adobe-3.0
%!PS-Adobe-3.0
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%Origin: 0
%%DocumentMedia: Default 165 165 0 () ()
%%BoundingBox: 0 0 165 165
%%LanguageLevel: 2
%%LanguageLevel: 2
%%Pages: 1
%%Page: 1 1
%%EndComments
Expand All @@ -16,7 +16,7 @@
%%BeginFeature: *PageSize Default
<< /PageSize [ sz sz ] /ImagingBBox null >> setpagedevice
%%EndFeature
%%BeginFunctions
%%BeginFunctions
/csquare {
newpath
0 0 moveto
Expand All @@ -27,15 +27,15 @@
setrgbcolor
fill
} def
/f {
/f {
0 0 0 csquare
1 0 translate
} def
/b {
/b {
1 0 translate
} def
/background {
1 1 1 csquare
} def
/background {
1 1 1 csquare
} def
/nl {
-33 -1 translate
Expand Down Expand Up @@ -85,5 +85,5 @@ b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b
%%EndBody
grestore
showpage
showpage
%%EOF
18 changes: 9 additions & 9 deletions QRCoderTests/PostscriptQRCodeRendererTests.can_render_postscript_qrcode_size.approved.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,11 +1,11 @@
%!PS-Adobe-3.0
%!PS-Adobe-3.0
%%Creator: QRCoder.NET
%%Title: QRCode
%%DocumentData: Clean7Bit
%%Origin: 0
%%DocumentMedia: Default 33 33 0 () ()
%%BoundingBox: 0 0 33 33
%%LanguageLevel: 2
%%LanguageLevel: 2
%%Pages: 1
%%Page: 1 1
%%EndComments
Expand All @@ -16,7 +16,7 @@
%%BeginFeature: *PageSize Default
<< /PageSize [ sz sz ] /ImagingBBox null >> setpagedevice
%%EndFeature
%%BeginFunctions
%%BeginFunctions
/csquare {
newpath
0 0 moveto
Expand All @@ -27,15 +27,15 @@
setrgbcolor
fill
} def
/f {
/f {
0 0 0 csquare
1 0 translate
} def
/b {
/b {
1 0 translate
} def
/background {
1 1 1 csquare
} def
/background {
1 1 1 csquare
} def
/nl {
-33 -1 translate
Expand Down Expand Up @@ -85,5 +85,5 @@ b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b nl
b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b b
%%EndBody
grestore
showpage
showpage
%%EOF
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