diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/qpdf/QPDF.hh | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh index a614e98a..78b4228c 100644 --- a/include/qpdf/QPDF.hh +++ b/include/qpdf/QPDF.hh @@ -112,8 +112,11 @@ class QPDF // Create a PDF from an input source that contains JSON as written // by writeJSON (or qpdf --json-output, version 2 or higher). The - // JSON must be a complete representation of a PDF. See "QPDF JSON - // Format" in the manual for details. + // JSON must be a complete representation of a PDF. See "qpdf + // JSON" in the manual for details. The input JSON may be + // arbitrarily large. QPDF does not load stream data into memory + // for more than one stream at a time, even if the stream data is + // specified inline. QPDF_DLL void createFromJSON(std::string const& json_file); QPDF_DLL @@ -122,24 +125,40 @@ class QPDF // Update a PDF from an input source that contains JSON in the // same format as is written by writeJSON (or qpdf --json-output, // version 2 or higher). Objects in the PDF and not in the JSON - // are not modified. See "QPDF JSON Format" in the manual for - // details. + // are not modified. See "qpdf JSON" in the manual for details. As + // with createFromJSON, the input JSON may be arbitrarily large. QPDF_DLL void updateFromJSON(std::string const& json_file); QPDF_DLL void updateFromJSON(std::shared_ptr<InputSource>); - // Write qpdf json format. The only supported version is 2. If - // wanted_objects is empty, write all objects. Otherwise, write - // only objects whose keys are in wanted_objects. Keys may be - // either "trailer" or of the form "obj:n n R". Invalid keys are - // ignored. + // Write qpdf json format to the pipeline "p". The only supported + // version is 2. The finish() method is called on the pipeline at + // the end. The decode_level parameter controls which streams are + // uncompressed in the JSON. Use qpdf_dl_none to preserve all + // stream data exactly as it appears in the input. The possible + // values for json_stream_data can be found in qpdf/Constants.h + // and correspond to the --json-stream-data command-line argument. + // If json_stream_data is qpdf_sj_file, file_prefix must be + // specified. Each stream will be written to a file whose path is + // constructed by appending "-nnn" to file_prefix, where "nnn" is + // the object number (not zero-filled). If wanted_objects is + // empty, write all objects. Otherwise, write only objects whose + // keys are in wanted_objects. Keys may be either "trailer" or of + // the form "obj:n n R". Invalid keys are ignored. This + // corresponds to the --json-object command-line argument. + // + // QPDF is efficient with regard to memory when writing, allowing + // you to write arbitrarily large PDF files to a pipeline. You can + // use a pipeline like Pl_Buffer or Pl_String to capture the JSON + // output in memory, but do so with caution as this will allocate + // enough memory to hold the entire PDF file. QPDF_DLL void writeJSON( int version, - Pipeline*, - qpdf_stream_decode_level_e, - qpdf_json_stream_data_e, + Pipeline* p, + qpdf_stream_decode_level_e decode_level, + qpdf_json_stream_data_e json_stream_data, std::string const& file_prefix, std::set<std::string> wanted_objects); |