Method and apparatus for associating with an electronic document a font subset containing select character forms which are different depending on location
A method and apparatus are provided for embedding a font subset in an electronic document. The method in one form includes analyzing a document having characters of a font set where characters may have different forms depending on the location of the character in a word or one or more ligatures represent a combination of characters. A font subset is created corresponding to only the character forms present in the document and the font subset is associated with the document. Advantageously, the embedded font subset only contains the font characters which are used in the document and not all characters which may be present in a complete font set for all font sets referenced in the document.
1. A computer-implemented method for font subsetting, wherein a computer is programmed to perform steps of the method and said method comprises:
analyzing, by a processor, for each of all multiple text fonts represented in a document, characters of a font set of the text of the document character by character and by character combinations to identify interdependence between the characters and determine the characters associated with glyphs having different forms at different locations of a character in a word or the font set where one or more ligatures represent a combination of characters, wherein analyzing includes determining if characters of one of the multiple text fonts include variants of a glyph and if characters of one of the multiple text fonts include a combination of characters that represent a single ligature;
creating a font subset containing shapes of the glyphs corresponding to only character forms present in the document identified in the analyzing of the text of the document thereby providing a font subset of a reduced size, wherein the font subset includes a ligature or a glyph that has different forms at different locations of a character in a word; and
associating the font subset with the document,
wherein said associating the font subset with the document comprises embedding the font subset in the document or transmitting the font subset along with the document.
2. The method of claim 1 , wherein said associating the font subset comprises storing the font subset within the document.
3. The method of claim 1 , wherein one or more of said characters have different positional glyph variants depending on the characters thereto and whether the character is an isolated, an initial, a medial or a final character of a word.
4. The method of claim 1 , wherein the combination of characters in the font set is represented by the single ligature in the font subset.
5. A computer-implemented method for font sub setting, wherein a computer is programmed to perform steps of the method and said method comprises:
analyzing, by a processor, for each of all multiple text fonts represented in a document, characters in the text of the document character by character and by character combinations to identify interdependence between the characters and determine the characters which have glyph forms corresponding to:
1) a location in which a character is located within a word or
2) a combination of character,
wherein analyzing includes determining if characters of one of the multiple text fonts include variants of a glyph and if characters of one of the multiple text fonts include a combination of characters that represent a single ligature;
creating a font character subset comprising only the glyph forms present in the document as identified from the analyzing of the text of the document thereby providing a font subset of a reduced size, wherein the font subset includes a ligature or a glyph that has different forms at different locations of a character in a word; and
associating the font character subset with the document, wherein said associating the font character subset with the document comprises embedding the font character subset in the document or transmitting the font subset along with the document.
6. The method of claim 5 , wherein one or more of said characters have different glyph forms depending on the characters adjacent thereto and whether the character is an isolated, an initial, a medial or a final character of a word.
7. The method of claim 6 , wherein the combination of characters is represented by the single ligature in the font character subset.
8. A non-transitory computer-readable medium comprising instructions for font subsetting, said instructions when executed by a processor perform a method comprising:
analyzing, for each of all multiple text fonts represented in a document, the text of the document comprising characters of a font set character by character and by character combinations to identify interdependence between the characters, wherein said characters comprise different forms at different locations of a character in a word or one or more ligatures which represent a combination of characters, wherein analyzing includes determining if characters of one of the multiple text fonts include variants of a glyph and if characters of one of the multiple text fonts include a combination of characters that represent a single ligature;
creating a font subset corresponding to only character forms present in the document identified in the analyzing of the text of the document to thereby provide a font subset of a reduced size, wherein the font subset includes a ligature or a glyph that has different forms at different locations of a character in a word; and associating the font subset with the document,
wherein said associating the font subset with the document comprises embedding the font subset in the document or transmitting the font subset along with the document.
9. The computer processor of claim 8 , wherein the font subset is transmitted as a separate data stream in a media presentation.
10. A computer system for font subsetting, said system comprising:
computer memory for storage and recall of text of a document comprising characters having glyph forms corresponding to:
a) a location in which a character is present within a word or
b) a combination of characters;
a processor for:
i) analyzing, for each of all multiple text fonts represented in the document, the text of the document character by character and by character combinations to identify interdependence between the characters and determine which glyphs are present therein, wherein analyzing includes determining if characters of one of the multiple text fonts include variants of a glyph and if characters of one of the multiple text fonts include a combination of characters that represent a single ligature;
ii) creating a subset of a font set corresponding to only character forms present in the text identified in the analyzing of the text of the document to thereby provide a font subset of a reduced size, wherein the font subset includes a ligature or a glyph that has different forms at different locations of a character in a word; and
iii) associating the subset of the font set with the document,
wherein said associating the subset of the font set with the document comprises embedding the subset of the font set in the document or transmitting the font subset along with the document.