Keywords and text strings The following keywords are predefined and should be used where appropriate.
Experience Cloud, marketing, data, and advertising solutions, document Cloud.
CIE-15.2, CIE, "Colorimetry, Second Edition".
It contains: Width 4 bytes Height 4 bytes Bit depth 1 byte Colour type 1 byte Compression method 1 byte Filter method 1 byte Interlace method 1 byte Width and height give the image dimensions in pixels.
Errors in a PNG datastream will fall into two general classes, transmission errors and syntax errors (see.8 Error handling ).Chunk Type A sequence of four bytes defining the chunk type.Unsigned arithmetic modulo 256 is used, so that both the inputs and outputs fit into bytes.Such extensions might be made to the standard either for deadly boss mods 4.52-r4442 experimental purposes or by organizations for internal use.
PNG decoders that provide colour printing facilities can use the facilities in Level 2 PostScript to specify image data in calibrated RGB space or in a device-independent colour space such as XYZ.
The only compression method defined in this International Standard is method 0 (zlib datastream with deflate compression, see.3: Other uses of compression ).
The equation for computing a composited sample value is: output alpha * foreground (1-alpha) * background where alpha and the input and output sample values are expressed as fractions in the range 0.
Such programs have enough information to write valid cHRM and gAMA chunks, and are strongly encouraged to do so automatically.
This allows PNG decoders to recover the original data losslessly even if the data had a sample depth not directly supported by PNG.Table.1 Types of ancillary information Type of information Description Background colour Solid background colour to be used when presenting the image if no better option is available.A mismatch indicates that the data or the CRC were corrupted in transit.Although this does not have too bad an effect on image quality, the time savings are small if alpha values of zero and one are treated as special cases as recommended here.In a PNG datastream transparency may be represented in one of four ways, depending on the PNG image type (see.3.2: Alpha separation and.3.5: Alpha compaction ).For example, if the PNG image is 16 by 16 pixels, then the third pass will be a reduced image of two scanlines, each containing four pixels (see figure.8 ).The most accurate scaling is achieved by the linear equation output floor(input * maxoutsample / maxinsample).5) where maxinsample (2sampledepth)-1 maxoutsample (2desired_sampledepth)-1 A slightly less accurate conversion is achieved by simply shifting right by (sampledepth - desired_sampledepth) places.The sPLT chunk may appear for any PNG colour type.No chunks or other content follow the iend chunk.