This is what a complete results report would look like when each of the fields controlling the output is specified and PDF Checker completes the review successfully.
Note the section at the top of the results output, the CHECKER_SUMMARY.
This is a summary list of the items that PDF Checker found when reviewing a PDF document, intended to be machine readable. But you might prefer to use the JSON output format instead.
You could set up a batch process to review a set of PDF documents stored in a server directory automatically, one by one. Then, you could add a step to your batch code that would identify the PDF documents that PDF Checker found with issues or problems, create an input JSON file listing those issues or problems, and send that JSON file list to PDF Optimizer. PDF Optimizer could then optimize each PDF document based on the items found by PDF Checker. Note that for documents that PDF Optimizer can improve, a statement appears, “canBeOptimized,” to make it easy detect documents that are candidates for optimization. The software also provides the size of the PDF source document, and a machine readable value, “sizeInBytes.” This allows you to scan the results to make decisions on document processing based on file size. For example, a PDF document that is only 10 KB probably isn’t worth optimizing.
Note that the metadata for the PDF document is provided at the top of the report. The “Trapped” parameter refers to the prepress workflow when printing in color. Trapping a document governs how the ink will appear on the page; colors are trapped by adjusting the shape of objects as they are printed on the page to avoid gaps from appearing. Trapping can be enabled by some software products that generate PDF documents, such as Adobe InDesign.
PDF Checker will determine if the PDF document claims PDF/A compliance, and provide the type of PDF/A file. If in fact the file is not PDF/A compliant, an error message will appear in the output report.
PDF Checker 2.1.0 Copyright 2018-2021 Datalogics, Inc. All Rights Reserved Wed Mar 17 11:07:33 2021 JSON Profile: everything.json Input Document: DocumentationExample.pdf PDF Version: 1.7 Claimed PDF/A Type: PDF/A-2a Conforms to Claimed PDF/A Type: False Author: John Smith Creation Date: 2020-Sep-08 13:13:58 Creator: Acrobat PDFMaker 15 for Word Keywords: Modification Date: 2020-Sep-08 13:14:04 Producer: Adobe PDF Library 18.0 Subject: Title: Trapped: File Size: 393 KB <<=CHECKER_SUMMARY_START=>> general:born-digital general:doess-not-conform-to-claimed-pdfa-type general:tagged-pdf userdata:contains-annots userdata:contains-annots-not-for-printing userdata:contains-metadata userdata:contains-transparency fonts:found-non-extractible-text fonts:uses-base14fonts-not-embedded fonts:uses-fonts-not-embedded cleanup:suboptimal-compression sizeInBytes:402518 canBeOptimized <<=CHECKER_SUMMARY_END=>> Optimization Assessment Document can be optimized with PDF Optimizer - see details below General Results Errors: Is not PDF/A conformant, see 'claimed-pdfa-type' in the Summary section for more details.: Total: (1 instance) Information: Document was born digital. It was produced from PDF authoring software and so it may contain text, images, tables, forms, and other objects. These types of PDFs typically do not require OCR. Is not PDF/A conformant: Total: (1 instance) Document contains tagged content Checks Completed: acroforms-type born-digital claims-pdfe-conformance claims-pdfua-conformance claims-pdfvt-conformance claims-pdfx-conformance contains-owner-password contains-signature damaged does-not-conform-to-claimed-pdfa-type image-only password-protected pdf-v2 tagged-pdf unable-to-open xfa-type How To Optimize: Document claims to be PDF/A-2a conformant, but it is not, try using PDF Optimizer to convert to a compliant PDF/A document. (1 instance) Userdata Results Errors: None Information: Contains annotations: SubType: Link (21 instances) Contains annotations that are set as invisible for printing: SubType: Link (21 instances) Contains metadata: SubType: XML, Update region size: 2048 (1 instance) Total: (1 instance) Contains transparency: Total: (1 instance) Checks Completed: contains-annots contains-annots-not-for-printing contains-annots-not-for-viewing contains-annots-without-normal-appearances contains-embedded-files contains-metadata contains-optional-content contains-private-data contains-transparency How To Optimize: Annotations can be removed using PDF Optimizer to save space. (21 instances) Annotations not intended for printing can be removed using PDF Optimizer to save space. (21 instances) Metadata can be removed using PDF Optimizer to save space. (1 instance) XMP Metadata padding can be removed using PDF Optimizer to save space. (1 instance) Transparency (which is not universally supported by PDF Viewers) can be flattened using PDF Optimizer. (1 instance) Fonts Results Errors: Uses Base 14 fonts not embedded in document: Arial-BoldMT (1 instance) ArialMT (1 instance) CourierNewPSMT (1 instance) Uses fonts not embedded in document: CenturyGothic (1 instance) CenturyGothic-Bold (1 instance) Information: Uses fonts that do not allow text to be extracted: HSODIF+SymbolMT, SubType: Type0 (1 instance) Checks Completed: fontdescriptor-missing-capheight fontdescriptor-missing-fields found-non-extractible-text uses-base14fonts-not-embedded uses-fonts-fully-embedded uses-fonts-not-embedded Objects Results Errors: None Information: None Checks Completed: contains-javascript-actions contains-thumbnails Cleanup Results Errors: None Information: Contains conservatively compressed streams: Uncompressed: (1 instance) Checks Completed: suboptimal-compression Image Results Errors: None Information: None Checks Completed: alternate-images Color Images Errors: None Information: None Checks Completed: image-depth resolution-too-high resolution-too-low uses-jpeg2000-compression Grayscale Images Errors: None Information: None Checks Completed: resolution-too-high resolution-too-low uses-jpeg2000-compression Monochrome Images Errors: None Information: None Checks Completed: resolution-too-high resolution-too-low uses-jbig2-compression