JPEG 2000 plugin supports to losslessly or lossy compress gray-scale,
RGB, and RGBA images with byte, unsigned short or short data type. It also
supports losslessly compress bilevel, and 8-bit indexed. The result data
is in the format of JP2 (JPEG 2000 Part 1 or baseline format).
Many encoding parameters for JPEG 2000 can be tile-component specific.
These parameters are marked as Yes in the column
TC_SPEC in the following parameter table.
They must be provided according to the pattern:
[<tile-component idx>] <param> (repeated as many time as needed),
where <tile-component idx> respect the following policy according to
the degree of priority:
Where the priorities of the specifications are:
(1) > (2) > (3) > (4), (">" means "overrides")
<idx>: "," separates indexes, "-" separates bounds of indexes list.
(for example, 0,2-4 means indexes 0,2,3 and 4).
JPEG 2000 Plugin Decoding Parameters
| Parameter Name | Description | TC_SPEC |
|---|
| encodingRate |
The bitrate in bits-per-pixel for encoding. Should be set when
lossy compression scheme is used. With the default value
Double.MAX_VALUE, a lossless compression will be done.
|
No |
| lossless |
Indicates using the loseless scheme or not. It is equivalent to
use reversible quantization and 5x3 integer wavelet filters. The
default is true.
|
No |
| componentTransformation |
Specifies to utilize the component transformation on some tiles.
If the wavelet transform is reversible (w5x3 filter), the Reversible
Component Transformation (RCT) is applied. If not reversible
(w9x7 filter), the Irreversible Component Transformation (ICT) is used.
|
Yes, Tile_Specific |
| filters |
Specifies which wavelet filters to use for the specified
tile-components. JPEG 2000 part I only supports w5x3 and w9x7 filters.
|
Yes |
| decompositionLevel |
Specifies the wavelet decomposition levels to apply to
the image. If it is 0, no wavelet transform is performed, in which
case the original image data will be sent to the encoder and an example
is the binary data. All components and all tiles have the same number
of decomposition levels. The default value is 5.
|
No |
| guardBits |
The number of bits used for each tile-component in the quantizer
to avoid overflow. It takes values in the range 0 through 7. The
default value is 2.
|
Yes |
| quantizationStep |
This parameter specifies the base normalized quantization step
size for the tiles/components. It is normalized to a dynamic range
of 1 in the image domain. This parameter is ignored in reversible
coding. The default value is 0.0078125.
|
Yes |
| quantizationType |
Specifies which quantization type to use for specified
tiles/components. Not specified for lossless compression. By default,
the quantization step size is "expounded". Supported quantization
types specification are : "reversible" (no quantization), "derived"
(derived quantization step size) and "expounded".
|
Yes |
| codeBlockSize |
Specifies the maximum code-block size to use for tile-component.
The maximum width and height is 1024, however the block size
(i.e. width x height) must not exceed 4096. The minimum width and
height is 4. The default values are (64, 64).
|
Yes |
| progressionType |
Specifies which type of progression should be used when generating
the codestream.
The format is [<tile index>]
res|layer|res-pos|pos-comp|comp-pos [res_start comp_start layer_end
res_end comp_end prog] [[res_start comp_start layer_end res_end
comp_end prog]...] [[<tile-component idx]...].
The value "res" generates a resolution progressive
codestream with the number of layers specified by "layers" parameter.
The value "layer" generates a layer progressive codestream with
multiple layers. In any case, the rate-allocation algorithm optimizes
for best quality in each layer. The quality measure is mean squared
error (MSE) or a weighted version of it (WMSE). If no progression
type is specified or imposed by other parameters, the default value
is "layer". It is also possible to describe progression order
changes. In this case, "res_start" is the index (from 0) of the
first resolution level, "comp_start" is the index (from 0) of the
first component, "layer_end" is the index (from 0) of the first layer
not included, "res_end" is the index (from 0) of the first
resolution level not included, "comp_end" is index (from 0) of
the first component not included and "prog" is the progression type
to be used for the rest of the tile/image. Several progression
order changes can be specified, one after the other.
|
Yes |
| packPacketHeaderInTile |
Indicates that the packet headers are packed in the tiles' headers.
The default is false.
|
No |
| packPacketHeaderInMain |
Indicates that the packet headers are packed in the main header.
The default is false.
|
No |
| packetPerTilePart |
Specifies the maximum number of packets to be put into one tile-part.
Zero means putting all packets in the first tile-part of each tile.
|
No |
| ROIs |
Specifies ROIs shape and location. The component index specifies
which components contain the ROI. If this parameter is used, the
codestream is layer progressive by default unless it is overridden by
the progressionType. A rectanglar or circular ROI can be
specified in the format: [<component idx>] R <left>
<top> <width> <height> or [<component idx>] C
<center x> <center y> <radius>. An arbitrary shape
can be assigned by [<component idx>] A <PGM file>
|
Yes, component-specified |
| startLevelROI |
This parameter defines the lowest resolution levels to belong to
the ROI. By doing this, it is possible to avoid getting
information for the ROI at an early stage of transmission.
startLevelROI = 0 means the lowest resolution level belongs to
the ROI, 1 means the second lowest etc. The default values, -1,
deactivates this parameter.
|
No |
| alignROI |
By specifying this parameter, the ROI mask will be limited to
covering only entire code-blocks. The ROI coding can then be
performed without any actual scaling of the coefficients but by
instead scaling the distortion estimates.
|
No |
| bypass |
Uses the lazy coding mode with the entropy coder. This will bypass
the MQ coder for some of the coding passes, where the distribution
is often close to uniform. Since the MQ codeword will be terminated
at least once per lazy pass, it is important to use an efficient
termination algorithm, methodForMQTermination.
true enables, and false disables it. The default value is false.
|
Yes |
| resetMQ |
If this is enabled the probability estimates of the MQ coder are
reset after each arithmetically coded (i.e. non-lazy) coding pass.
true enables, and false disables it. The default value is false.
|
Yes |
| terminateOnByte |
If this is enabled the codeword (raw or MQ) is terminated on a byte
boundary after each coding pass. In this case it is important to use
an efficient termination algorithm, "methodForMQTermination".
true enables, and false disables it. The default value is false.
|
Yes |
| causalCXInfo |
Uses vertically stripe causal context formation. If this is
enabled the context formation process in one stripe is independant of
the next stripe (i.e. the one below it). true enables, and false
disables it. The default value is false.
|
Yes |
| codeSegSymbol |
Inserts an error resilience segmentation symbol in the MQ codeword
at the end of each bit-plane (cleanup pass). Decoders can use this
information to detect and conceal errors. true enables, and false
disables it. The default value is false.
|
Yes |
| methodForMQTermination |
Specifies the algorithm used to terminate the MQ codeword. The
most efficient one is "near_opt", which delivers a codeword which
in almost all cases is the shortest possible. The "easy" is a
simpler algorithm that delivers a codeword length that is close
to the previous one (in average 1 bit longer). The "predict" is
almost the same as the "easy" but it leaves error resilient
information on the spare least significant bits (in average 3.5 bits),
which can be used by a decoder to detect errors. The "full" algorithm
performs a full flush of the MQ coder and is highly inefficient. It
is important to use a good termination policy since the MQ codeword
can be terminated quite often, specially if the "bypass" or
"terminateOnByte" parameters are enabled (in the normal case it would
be terminated once per code-block, while "terminateOnByte" is specified
it will be done almost 3 times per bit-plane in each code-block).
The default value is "near_opt".
|
Yes |
| methodForMQLengthCalc |
Specifies the algorithm to use in calculating the necessary MQ
length for each decoding pass. The best one is "near_opt", which
performs a rather sophisticated calculation and provides the best
results. The "lazy_good" and "lazy" are very simple algorithms
that provide rather conservative results. "lazy_good" performs
slightly better. Please use the default unless the experiments
show the benefits of different length calculation algorithms.
The default value is "near_opt".
|
Yes |
| precinctPartition |
Specifies precinct partition dimensions for tiles/components. They
are stored from those applied to the highest resolution to those
applied to the remaining resolutions in decreasing order. If less
values than the number of decomposition levels are specified, then
the last two values are used for the remaining resolutions.
|
Yes |
| layers |
Explicitly specifies the codestream layer formation parameters.
The rate (double) parameter specifies the bitrate to which the first
layer should be optimized. The layers (int) parameter, if present,
specifies the number of extra layers that should be added for
scalability. These extra layers are not optimized. Any extra rate
and layers parameters add more layers, in the same way. An
additional layer is always added at the end, which is optimized
to the overall target bitrate of the bit stream. Any layers
(optimized or not) whose target bitrate is higher that the overall
target bitrate are silently ignored. The bitrates of the extra layers
that are added through the layers parameter are approximately
log-spaced between the other target bitrates. If several (rate, layers)
constructs appear the rate parameters must appear in increasing order.
The rate allocation algorithm ensures that all coded layers have a
minimal reasonable size, if not these layers are silently ignored.
Default: 0.015 +20 2.0 +10.
|
No |
| SOP |
Specifies whether start of packet (SOP) markers should be used.
true enables, false disables it. The default value is false.
|
Yes |
| EPH |
Specifies whether end of packet header (EPH) markers should be used.
true enables, false disables it. The default value is false.
|
Yes |
