class final Core · roukmoute/pdf 0.6.2

PDF\Specification\Dictionary\ImageDictionaryTable89\BitsPerComponentEntry
Table 89, /BitsPerComponent; PDF type: integer; Required except for image masks and images that use the JPXDecode filter.

Lire la déclaration source ↗

Héritage et contrats

Parent : PDF\Specification\SchemaEntry

Définition dans la norme

Tableau 89 · Additional Entries Specific to an Image Dictionary
ISO 32000-1:2008, §8.9.5.1 · page PDF 215 ↗

/BitsPerComponent integer

(Required except for image masks and images that use the JPXDecode filter) The number of bits used to represent each colour component. Only a single value shall be specified; the number of bits shall be the same for all colour components. The value shall be 1, 2, 4, 8, or (in PDF 1.5) 16. If ImageMask is true, this entry is optional, but if specified, its value shall be 1. If the image stream uses a filter, the value of BitsPerComponent shall be consistent with the size of the data samples that the filter delivers. In particular, a CCITTFaxDecode or JBIG2Decode filter shall always deliver 1-bit samples, a RunLengthDecode or DCTDecode filter shall always deliver 8-bit samples, and an LZWDecode or FlateDecode filter shall deliver samples of a specified size if a predictor function is used. If the image stream uses the JPXDecode filter, this entry is optional and shall be ignored if present. The bit depth is determined by the conforming reader in the process of decoding the JPEG2000 image.

Qualificateur : Required except for image masks and images that use the JPXDecode filter

Les descriptions conditionnelles restent traçables. La présence d’une définition ne réalise pas à elle seule un codec, une signature ou tous les traitements du format. Lire la couverture.

Construction

__construct()

Déclarée par PDF\Specification\Dictionary\ImageDictionaryTable89\BitsPerComponentEntry · Voir le code ↗

Méthodes héritées

3 méthodes des parents et contrats

definition()

public function definition(): PDF\Specification\EntryDefinition

Déclarée par PDF\Specification\SchemaEntry · Voir le code ↗

key()

public function key(): PDF\Syntax\Object\NameType

Déclarée par PDF\Syntax\Object\DictionaryObject\Entry · Voir le code ↗

value()

public function value(): PDF\Syntax\FileStructure\BasicType

Déclarée par PDF\Syntax\Object\DictionaryObject\Entry · Voir le code ↗

Propriétés

Constantes