cpdf -print-struct-tree in.pdf
cpdf -extract-struct-tree in.pdf -o out.json
cpdf -replace-struct-tree in.json in.pdf -o out.pdf
cpdf -remove-struct-tree in.pdf -o out.pdf
cpdf -mark-as-artifact in.pdf -o out.pdf
cpdf -verify "PDF/UA-1(matterhorn)" [-json] in.pdf
cpdf -verify "PDF/UA-1(matterhorn)" -verify-single <test> [-json] in.pdf
cpdf -mark-as ["PDF/UA-1" | "PDF/UA-2"] in.pdf -o out.pdf
cpdf -remove-mark ["PDF/UA-1" | "PDF/UA-2"] in.pdf -o out.pdf
cpdf -create-pdf-ua-<1|2> <title> [-create-pdf-pages <n>] [-create-pdf-papersize <paper size>] -o out.pdf
PDF/UA (Universal Accessibility) is a PDF subformat whose rules consist of a set of machine-checkable and human-checkable-only requirements to make PDF documents accessible for all users - for example, those using screen readers. Cpdf has some basic facilities for manipulating the extra PDF constructs which are used in (amongst others) PDF/UA, and a basic verifier for many of the machine-checkable requirements.
In a PDF document, the optional Structure Tree is a parallel construct which describes the logical structure of a document (as opposed to the information for rendering the document on the screen or printing it out, which every PDF of course contains.)
We can print an abbreviated form of the structure tree to standard output:
cpdf -print-struct-tree in.pdf
This might yield:
StructTreeRoot Document Sect P (1) Span (1) Figure (1) Sect H1 (2) TOC TOCI P Link (2) . . . . . .
The numbers in parentheses are the page numbers for structure elements, where present. We can extract the full structure tree to JSON for inspection or manupulation:
cpdf -extract-struct-tree in.pdf -o out.json
Here is a typical fragment:
[
[ 0, { "/CPDFJSONformatversion": 1, "/CPDFJSONpageobjnumbers": [ 52 ] } ],
[
102,
{
"/Type": { "N": "/StructElem" },
"/S": { "N": "/TD" },
"/P": 98,
"/Pg": 52,
"/K": { "I": 38 },
"/T": { "U": "row #7, col #3" },
"/A": {
"/O": { "N": "/Layout" },
"/Height": { "F": 18.28 },
"/Width": { "F": 73.07689999999999 }
}
}
],
[
15,
{
"/Type": { "N": "/StructElem" },
"/S": { "N": "/TD" },
"/P": 59,
"/Pg": 52,
"/K": { "I": 20 },
"/T": { "U": "row #3, col #5" },
"/A": {
"/O": { "N": "/Layout" },
"/Height": { "F": 18.28 },
"/Width": { "F": 73.07689999999999 }
}
}
],
...
This JSON file contains the structure tree objects from the file, using the format described in chapter 15. There is a special entry in object 0 which gives the key to the page object numbers. In this example, there is one page with object number 52.
This JSON file can be edited, for example to change text strings, and reapplied to the same file from which it was extracted:
cpdf -replace-struct-tree out.json in.pdf -o out.pdf
If extra objects are required, they should be introduced with negative object numbers: Cpdf will renumber them on import so as not to clash with any existing numbers.
To remove a structure tree from a PDF, we can use -remove-struct-tree:
cpdf -remove-struct-tree in.pdf -o out.pdf
This removes the structure tree and all references to it, including from inside page content. In addition we can, afterward, use -mark-as-artifact:
cpdf -mark-as-artifact in.pdf -o out.pdf
This marks all content in the file as being an artifact.
Cpdf contains a new, experimental verifier for PDF/UA via most of the machine-checkable subset of the Matterhorn Protocol, a list of checks based on the PDF/UA-1 specification. For example, we can run:
cpdf -verify "PDF/UA-1(matterhorn)" in.pdf
We see:
06-001 UA1:7.1-8 Document does not contain an XMP metadata stream
07-001 UA1:7.1-9 ViewerPreferences dictionary of the Catalog dictionary does
not contain a DisplayDocTitle entry
11-006 UA1:7.2-3 Natural language for document metadata cannot be determined.
("No top-level /Lang")
28-004 UA1:7.18.1-4 An annotation, other than of subtype Widget, does not
have a Contents entry and does not have an alternative description (in the
form of an Alt entry in the enclosing structure element).
28-008 UA1:7.18.3-1 A page containing an annotation does not contain a Tabs
entry
28-011 UA1:7.18.5-1 A link annotation is not nested within a <Link> tag.
28-012 UA1:7.18.5-2 A link annotation does not include an alternate
description in its Contents entry.
The first column here is the Matterhorn Protocol checkpoint, the second the reference in the PDF/UA-1 standard docunment, the third the textual description from the Matterhorn Protocol, and an optional fourth (in parentheses) any extra information available.
The same information is available in JSON format by adding -json to the command line:
[
{
"name": "06-001",
"section": "UA1:7.1-8",
"error": "Document does not contain an XMP metadata stream",
"extra": null
},
{
"name": "07-001",
"section": "UA1:7.1-9",
"error": "ViewerPreferences dictionary of the Catalog dictionary does not
contain a DisplayDocTitle entry",
"extra": null
},
{
"name": "11-006",
"section": "UA1:7.2-3",
"error": "Natural language for document metadata cannot be determined.",
"extra": "No top-level /Lang"
},
{
"name": "28-004",
"section": "UA1:7.18.1-4",
"error": "An annotation, other than of subtype Widget, does not have a
Contents entry and does not have an alternative description (in the form of
an Alt entry in the enclosing structure element).",
"extra": null
},
{
"name": "28-008",
"section": "UA1:7.18.3-1",
"error": "A page containing an annotation does not contain a Tabs entry",
"extra": null
},
{
"name": "28-011",
"section": "UA1:7.18.5-1",
"error": "A link annotation is not nested within a <Link> tag.",
"extra": null
},
{
"name": "28-012",
"section": "UA1:7.18.5-2",
"error": "A link annotation does not include an alternate description in
its Contents entry.",
"extra": null
}
If verifying many files for a single fault, we may choose which test to run by adding -verify-single <testname> to the command line. For example:
cpdf -verify "PDF/UA-1(matterhorn)" -verify-single "28-012" in.pdf
Presently, Matterhorn tests 31-001–016,018,030 are unimplemented. Matterhorn tests 31-027,10-001,11-001–005 are partially implemented. All others are implemented.
Once we are sure a file complies to PDF/UA, in terms of both machine and human checks, we can mark it as such:
cpdf -mark-as "PDF/UA-1" in.pdf -o out.pdf
Or, for the more recent PDF/UA-2 standard:
cpdf -mark-as "PDF/UA-2" in.pdf -o out.pdf
To remove such a marker we can use, for example:
cpdf -remove-mark "PDF/UA-1" in.pdf -o out.pdf
The -process-struct-trees option should always be used in conjunction with any splitting or merging command to preserve PDF/UA compliance. Sometimes -subformat may be required too. Details are given in chapter 2.
To create a new PDF/UA-1 file, with A4 portrait paper, one page, and the title "My Book", we may write:
cpdf -create-pdf-ua-1 "My Book" -o out.pdf
A title is needed for every PDF/UA document (even a blank one) for it to meet the standard. For PDF/UA-2, use -create-pdf-ua-2 instead. To make it valid, you must also draw a top-level PDF/UA-2 Document tag as described below i.e:
cpdf -create-pdf-ua-2 "My Book" AND -draw -draw-struct-tree -namespace PDF2 -stag Document -end-stag -o out.pdf
Cpdf can add PDF/UA structure data when drawing on new PDF/UA files. For example the following produces a valid PDF/UA-1 file with structure information:
cpdf -create-pdf-ua-1 "Hello" AND -embed-std14 /path/to/fonts -draw-struct-tree -draw -bt -text "Hello, World" -et -o out.pdf
Note we had to specify embedded fonts to make this a valid PDF/UA-1 file. To make a valid PDF/UA-2 file we must also add a top-level Document structure tag with the appropriate namespace. Here is the PDF/UA-2 version of our file:
cpdf -create-pdf-ua-2 "Hello" AND -embed-std14 /path/to/fonts -draw-struct-tree -draw -namespace PDF2 -stag Document -namespace PDF -bt -text "Hello, World" -et -end-stag -o out.pdf
See chapter 18 for more details about adding structure information when drawing.
Remediation of a file which claims to match PDF/UA but which does not (either failing human or mechanical tests) is a complex topic. In this section, we list possible remediations for a file which fails mechanical verification with Cpdf or another verification tool. Sometimes these will be clear and simple – for example where some piece of document metadata is missing – and sometimes they will be almost impossible. Of course, often the truth lies between those two extremes.
When all else fails, it may be possible to modify the basic structures of the PDF manually. This may be done by extracting the PDF to JSON using -output-json from chapter 15, modifying the file manually in a text editor or automatically with a JSON processing tool such as jq and converting back to a PDF with -j. If the remediation requires altering page content streams, the option -output-json-parse-content-streams may be used.
The following table lists each mechanically-verifiable test from the Matterhorn protocol. For each, we give the number, description from the Matterhorn protocol, and the reference into the PDF/UA standard. Then we describe, if possible, how to use Cpdf to remediate the failure. Sometimes this is a definitive command, sometimes a last-ditch attempt to re-process the file (to embed missing fonts or correct font structures, for example) and sometimes simply a direction to try the manual remediation procedure described above.
| Number |
Description | Reference |
| 01-003 |
Content marked as Artifact is present inside tagged content. | UA1:7.1-1 |
| 01-004 |
Tagged content is present inside content marked as Artifact. | UA1:7.1-1 |
| 01-005 |
Content is neither marked as Artifact nor tagged as real content. | UA1:7-1-2 |
|
File does not meet Tagged PDF standard - only manual remediation possible (see description
above this table).
| ||
| 01-007 |
Suspects entry has a value of true. | UA1:7-1-11 |
|
If you are sure the file conforms to tagged PDF conventions, use cpdf -replace-obj
/Root/MarkInfo/Suspects=false in.pdf -o out.pdf.
| ||
| 02-001 |
One or more non-standard tag’s mapping does not terminate with a standard type. | UA1:7.1-3 |
| 02-003 |
A circular mapping exists. | UA1:7.1-3 |
| 02-004 |
One or more standard types are remapped. | UA1:7.1-4 |
|
File does not meet PDF/UA tagging standard - only manual remediation possible (see
description above this table).
| ||
| 06-001 |
Document does not contain an XMP metadata stream | UA1:7.1-8 |
|
Create XMP metadata from any existing old-style metadata in the file with cpdf
-create-metadata in.pdf -o out.pdf. This may lead to further verification errors due
to empty metadata entries.
| ||
| 06-002 |
The XMP metadata stream in the Catalog dictionary does not include the PDF/UA identifier. | UA1:5 |
|
Mark the file as PDF/UA using cpdf -mark-as ["PDF/UA-1" | "PDF/UA-2"] in.pdf
-o out.pdf.
| ||
| 06-003 |
XMP metadata stream does not contain dc:title | UA1:7.1-8 |
|
Add a title using cpdf -set-title "My title" -also-set-xmp in.pdf -o
out.pdf.
| ||
| 07-001 |
ViewerPreferences dictionary of the Catalog dictionary does not contain a DisplayDocTitle entry | UA1:7.1-9 |
|
Add the entry with cpdf -display-doc-title true in.pdf -o out.pdf.
| ||
| 07-002 |
ViewerPreferences dictionary of the Catalog dictionary contains a DisplayDocTitle entry with a value of false | UA1:7.1-9 |
|
Replace the entry with cpdf -display-doc-title true in.pdf -o out.pdf.
| ||
| 09-004 |
A table-related structure element is used in a way that does not conform to the syntax defined in ISO 32000-1, Table 337. | UA1-7.2-1 |
| 09-005 |
A list-related structure element is used in a way that does not conform to Table 336 in ISO 32000-1. | UA1-7.2-1 |
| 09-006 |
A TOC-related structure element is used in a way that does not conform to Table 333 in ISO 32000-1. | UA1-7.2-1 |
| 09-007 |
A Ruby-related structure element is used in a way that does not conform to Table 338 in ISO 32000-1. | UA1-7.2-1 |
| 09-008 |
A Warichu-related structure element is used in a way that does not conform to Table 338 in ISO 32000-1. | UA1-7.2-1 |
|
File does not meet PDF/UA tagging standard - only manual remediation possible (see
description above this table).
| ||
| 10-001 |
Character code cannot be mapped to Unicode. | UA1:7.2-2 |
|
It is possible that reprocessing the file with gs using cpdf in.pdf -gs gs
-gs-malformed-force -o out.pdf [-gs-quiet] will correct the fonts.
| ||
| 11-001 |
Natural language for text in page content cannot be determined. | UA1:7.2-3 |
| 11-002 |
Natural language for text in Alt, ActualText and E attributes cannot be determined. | UA1:7.2-3 |
| 11-003 |
Natural language in the Outline entries cannot be determined. | UA1:7.2-3 |
| 11-004 |
Natural language in the Contents entry for annotations cannot be determined. | UA1:7.2-3 |
| 11-005 |
Natural language in the TU entry for form fields cannot be determined. | UA1:7.2-3 |
| 11-006 |
Natural language for document metadata cannot be determined. | UA1:7.2-3 |
|
Assuming the document is all in a single language, set the top-level language with,
for example, cpdf -set-language "en-US" in.pdf -o out.pdf. If the document
contains multiple languages, only manual remediation is possible.
| ||
| 13-004 |
<Figure> tag alternative or replacement text missing. | UA1:7.3-3 |
| 14-002 |
Does use numbered headings, but the first heading tag is not <H1>. | UA1:7.4.2-1 |
| 14-003 |
Numbered heading levels in descending sequence are skipped (Example: <H3> follows directly after <H1>). | UA1:7.4-1 |
| 14-006 |
A node contains more than one <H> tag. | UA1:7.4.4-1 |
| 14-007 |
Document uses both <H> and <H#> tags. | UA1:7.4.4-3 |
| 15-003 |
In a table not organized with Headers attributes and IDs, a <TH> cell does not contain a Scope attribute. | UA1:7.5-2 |
| 17-002 |
<Formula> tag is missing an Alt attribute. | UA1:7.7-1 |
|
File does not meet PDF/UA standard - only manual remediation possible (see description
above this table). Alternatively, edit the tree manually using -extract-struct-tree and
-replace-struct-tree from this chapter.
| ||
| 17-003 |
Unicode mapping requirements are not met. | UA1:7.7-2 |
|
It is possible that reprocessing the file with gs using cpdf in.pdf -gs gs
-gs-malformed-force -o out.pdf [-gs-quiet] will correct the fonts.
| ||
| 19-003 |
ID entry of the <Note> tag is not present. | UA1:7.9-2 |
| 19-004 |
ID entry of the <Note> tag is non-unique. | UA1:7.9-2 |
| 20-001 |
Name entry is missing or has an empty string as its value in an Optional Content Configuration Dictionary in the Configs entry in the OCProperties entry in the Catalog dictionary. | UA1:7.10-1 |
| 20-002 |
Name entry is missing or has an empty string as its value in an Optional Content Configuration Dictionary that is the value of the D entry in the OCProperties entry in the Catalog dictionary. | UA1:7.10-1 |
|
File does not meet PDF/UA standard - only manual remediation possible (see description
above this table). Alternatively, edit the tree manually using -extract-struct-tree and
-replace-struct-tree from this chapter.
| ||
| 20-003 |
An AS entry appears in an Optional Content Configuration Dictionary. | UA1:7.10-2 |
|
File does not meet PDF/UA standard - only manual remediation possible (see description
above this table).
| ||
| 21-001 |
The file specification dictionary for an embedded file does not contain F and UF entries. | UA1:7.11-1 |
|
File does not meet PDF/UA standard - only manual remediation possible (see description
above this table). Alternatively, edit the tree manually using -extract-struct-tree and
-replace-struct-tree from this chapter.
| ||
| 25-001 |
File contains the dynamicRender element with value “required”. | UA1:7.15-1 |
|
Not remediable, unless actually a wrong marker. This is an interactive PDF form which likely
only works with Adobe Acrobat. If the marker is actually wrong, it may be edited manually
inside the XML stream using the instructions above.
| ||
| 26-001 |
The file is encrypted but does not contain a P entry in its encryption dictionary. | UA1:7.16-1 |
| 26-002 |
The file is encrypted and does contain a P entry but the 10th bit position of the P entry is false. | UA1:7.16-1 |
|
Re-encrypt the file with Cpdf as described in Chapter 4.
| ||
| 28-002 |
An annotation, other than of subtype Widget, Link and PrinterMark, is not a direct child of an <Annot> structure element. | UA1:7.18.1-2 |
| 28-004 |
An annotation, other than of subtype Widget, does not have a Contents entry and does not have an alternative description (in the form of an Alt entry in the enclosing structure element). | UA1:7.18.1-4 |
| 28-005 |
A form field does not have a TU entry and does not have an alternative description (in the form of an Alt entry in the enclosing structure element). | UA1:7.18.1-4 |
|
File does not meet PDF/UA standard - only manual remediation possible (see description
above this table). Alternatively, edit the tree manually using -extract-struct-tree and
-replace-struct-tree from this chapter.
| ||
| 28-006 |
An annotation with subtype undefined in ISO 32000 does not meet 7.18.1. | UA1:7.18.2-1 |
| 28-007 |
An annotation of subtype TrapNet exists. | UA1:7.18.2-2 |
| 28-008 |
A page containing an annotation does not contain a Tabs entry | UA1:7.18.3-1 |
| 28-009 |
A page containing an annotation has a Tabs entry with a value other than S. | UA1:7.18.3-1 |
|
If annotations are not required, they may
be removed with cpdf -remove-annotations in.pdf -o out.pdf. Alternatively, use
-output-annotations-json and -set-annotations-json as described in Chapter 10
to remove one or more specific annotations.
| ||
| 28-010 |
A widget annotation is not nested within a <Form> tag. | UA1:7.18.4-1 |
| 28-011 |
A link annotation is not nested within a <Link> tag. | UA1:7.18.5-1 |
|
If annotations are not required, they may be removed with cpdf -remove-annotations
in.pdf -o out.pdf. Alternatively,
use -output-annotations-json and -set-annotations-json as described in Chapter
10 to remove one or more specific annotations. Alternatively, edit the tree manually using
-extract-struct-tree and -replace-struct-tree from this chapter.
| ||
| 28-012 |
A link annotation does not include an alternate description in its Contents entry. | UA1:7.18.5-2 |
| 28-014 |
CT entry is missing from the media clip data dictionary. | |
| 28-015 |
Alt entry is missing from the media clip data dictionary. | UA1:7.18.6.2-1 |
| 28-016 |
File attachment annotations do not conform to 7.11. | UA1:7.18.7-1 |
|
If annotations are not required, they may
be removed with cpdf -remove-annotations in.pdf -o out.pdf. Alternatively, use
-output-annotations-json and -set-annotations-json as described in Chapter 10
to remove one or more specific annotations.
| ||
| 28-017 |
A PrinterMark annotation is included in the logical structure. | UA1:7.18.8-1 |
|
If annotations are not required, they may be removed with cpdf -remove-annotations
in.pdf -o out.pdf. Alternatively,
use -output-annotations-json and -set-annotations-json as described in Chapter
10 to remove one or more specific annotations. Alternatively, edit the tree manually using
-extract-struct-tree and -replace-struct-tree from this chapter.
| ||
| 28-018 |
The appearance stream of a PrinterMark annotation is not marked as Artifact. | UA1:7.18.8-2 |
|
If annotations are not required, they may
be removed with cpdf -remove-annotations in.pdf -o out.pdf. Alternatively, use
-output-annotations-json and -set-annotations-json as described in Chapter 10
to remove one or more specific annotations.
| ||
| 30-001 |
A reference XObject is present. | UA1:7.2 |
|
A reference XObject references a page in another file. May be cut out manually using the
manual remediation instructions above.
| ||
| 30-002 |
Form XObject contains MCIDs and is referenced more than once. | UA1:7.21.3.1-1 |
|
Unlikely to be remediable: the only option is to manually remove them, but this would then
result in a tag tree pointing to non-existent MCIDs, which would be another kind of invalidity.
Any PDF producer creating Tagged PDF with MCIDs like this is simply broken.
| ||
| 31-001 |
A Type 0 font dictionary with encoding other than Identity-H and Identity-V has values for Registry in both CIDSystemInfo dictionaries that are not identical. | UA1:7.21.3-1 |
| 31-002 |
A Type 0 font dictionary with encoding other than Identity-H and Identity-V has values for Ordering in both CIDSystemInfo dictionaries that are not identical. | UA1:7.21.3.1-1 |
| 31-003 |
A Type 0 font dictionary with encoding other than Identity-H and Identity-V has a value for Supplement in the CIDSystemInfo dictionary of the CID font that is less than the value for Supplement in the CIDSystemInfo dictionary of the CMap. | UA1:7.21.3.1-1 |
| 31-004 |
A Type 2 CID font contains neither a stream nor the name Identity as the value of the CIDToGIDMap entry. | UA1:7.21.3.2-1 |
| 31-005 |
A Type 2 CID font does not contain a CIDToGIDMap entry. | UA1:7.21.3.2-1 |
| 31-006 |
A CMap is neither listed as described in ISO 32000- 1:2008, 9.7.5.2, Table 118 nor is it embedded. | UA1:7.21.3.3-1 |
| 31-007 |
The WMode entry in a CMap dictionary is not identical to the WMode value in the CMap stream. | UA1:7.21.3.3-1 |
| 31-008 |
A CMap references another CMap which is not listed in ISO 32000-1:2008, 9.7.5.2, Table 118. | UA1:7.21.3.3-2 |
| 31-009 |
For a font used by text intended to be rendered the font program is not embedded. | UA1:7.21.4.1-1 |
| 31-011 |
For a font used by text the font program is embedded but it does not contain glyphs for all of the glyphs referenced by the text used for rendering. | UA1:7.21.4.1-3 |
| 31-012 |
The FontDescriptor dictionary of an embedded Type 1 font contains a CharSet string, but at least one of the glyphs present in the font program is not listed in the CharSet string. | UA1:7.21.4.2-1 |
| 31-013 |
The FontDescriptor dictionary of an embedded Type 1 font contains a CharSet string, but at least one of the glyphs listed in the CharSet string is not present in the font program. | UA1:7.21.4.2-2 |
| 31-014 |
The FontDescriptor dictionary of an embedded CID font contains a CIDSet string, but at least one of the glyphs present in the font program is not listed in the CIDSet string. | UA1:7.21.4.2-3 |
| 31-015 |
The FontDescriptor dictionary of an embedded CID font contains a CIDSet string, but at least one of the glyphs listed in the CIDSet string is not present in the font program. | UA1:7.21.4.2-4 |
| 31-016 |
For one or more glyphs, the glyph width information in the font dictionary and in the embedded font program differ by more than 1/1000 unit. | UA1:7.21.5-1 |
| 31-017 |
A non-symbolic TrueType font is used for rendering, but none of the cmap entries in the embedded font program is a non-symbolic cmap. | UA1:7.21.6-1 |
| 31-018 |
A non-symbolic TrueType font is used for rendering, but for at least one glyph to be rendered the glyph cannot be looked up by any of the non-symbolic cmap entries in the embedded font program. | UA1:7.21.6-2 |
| 31-019 |
The font dictionary for a non-symbolic TrueType font does not contain an Encoding entry. | UA1:7.21.6-3 |
| 31-020 |
The font dictionary for a non-symbolic TrueType font contains an Encoding dictionary which does not contain a BaseEncoding entry. | UA1:7.21.6-4 |
| 31-021 |
The value for either the Encoding entry or the BaseEncoding entry in the Encoding dictionary in a non-symbolic TrueType font dictionary is neither MacRomanEncoding nor WinAnsiEncoding. | UA1:7.21.6-5 |
| 31-022 |
The Differences array in the Encoding entry in a non-symbolic TrueType font dictionary contains one or more glyph names which are not listed in the Adobe Glyph List. | UA1:7.21.6-6 |
| 31-023 |
The Differences array is present in the Encoding entry in a non-symbolic TrueType font dictionary but the embedded font program does not contain a (3,1) Microsoft Unicode cmap. | UA1:7.21.6-7 |
| 31-024 |
The Encoding entry is present in the font dictionary for a symbolic TrueType font. | UA1:7.21.6-8 |
| 31-025 |
The embedded font program for a symbolic TrueType font contains no cmap. | UA1:7.21.6-9 |
| 31-026 |
The embedded font program for a symbolic TrueType font contains more than one cmap, but none of the cmap entries is a (3,0) Microsoft Symbol cmap. | UA1:7.21.6-10 |
| 31-027 |
A font dictionary does not contain the ToUnicode entry and none of the following is true: the font uses MacRomanEncoding, MacExpertEncoding or WinAnsiEncoding; the font is a Type 1 or Type 3 font and the glyph names of the glyphs referenced are all contained in the Adobe Glyph List or the set of named characters in the Symbol font, as defined in ISO 32000-1:2008, Annex D; the font is a Type 0 font, and its descendant CIDFont uses Adobe-GB1, Adobe-CNS1, Adobe-Japan1 or Adobe-Korea1 character collections; the font is a non-symbolic TrueType font. | UA1:7.21.7-1 |
| 31-028 |
One or more Unicode values specified in the ToUnicode CMap are zero (0). | UA1:7.21.7-2 |
| 31-029 |
One or more Unicode values specified in the ToUnicode CMap are equal to either U+FEFF or U+FFFE. | UA1:7.21.7-3 |
| 31-030 |
One or more characters used in text showing operators reference the .notdef glyph. | UA1:7.21.8-1 |
|
It is possible that reprocessing the file with gs using cpdf in.pdf -gs gs
-gs-malformed-force -o out.pdf [-gs-quiet] will correct the fonts.
| ||