| java.lang.Object
 jj2000.j2k.entropy.encoder.LayersInfo
| LayersInfo | | public class LayersInfo (Code) | | This class stores the specification of a layer distribution in the
bit stream. The specification is made of optimization points and a number of
extra layers to add between the optimization points. Each optimization
point creates a layer which is optimized by the rate allocator to the
specified target bitrate. The extra layers are added by the rate allocator
between the optimized layers, with the difference that they are not
optimized (i.e. they have no precise target bitrate).
The overall target bitrate for the bit stream is always added as the last
optimization point without any extra layers after it. If there are some
optimization points whose target bitrate is larger than the overall target
bitrate, the overall target bitrate will still appear as the last
optimization point, even though it does not follow the increasing target
bitrate order of the other optimization points. The rate allocator is
responsible for eliminating layers that have target bitrates larger than
the overall target bitrate.
Optimization points can be added with the addOptPoint() method. It takes
the target bitrate for the optimized layer and the number of extra layers
to add after it.
Information about the total number of layers, total number of
optimization points, target bitrates, etc. can be obtained with the other
methods.
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| Field Summary | |
| int | extralyrs
The number of extra layers to be added after an optimized layer. | | int | nopt
| | float | optbrate
The target bitrate to which specified layers should be optimized. | | float | totbrate
| | int | totlyrs
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| Constructor Summary | |
| public | LayersInfo(float brate)
Creates a new LayersInfo object. |
| Method Summary | |
| public void | addOptPoint(float brate, int elyrs)
Adds a new optimization point, with target bitrate 'brate' and with
'elyrs' (unoptimized) extra layers after it. | | public int | getExtraLayers(int n)
Returns the number of extra layers to add after the optimization point
'n', but before optimization point 'n+1'. | | public int | getNOptPoints()
Returns the number of layers to optimize, or optimization points, as
specified by this object. | | public float | getTargetBitrate(int n)
Returns the target bitrate of the optmimization point 'n'.
Parameters:
n - The optimization point index (starts at 0). | | public float | getTotBitrate()
Returns the overall target bitrate for the entire bit stream. | | public int | getTotNumLayers()
Returns the total number of layers, according to the layer
specification of this object and the overall target bitrate. |
| extralyrs | | int extralyrs(Code) | | The number of extra layers to be added after an optimized layer. After
the layer that is optimized to optbrate[i], extralyrs[i] extra layers
should be added. These layers are allocated between the bitrate
optbrate[i] and the next optimized bitrate optbrate[i+1] or, if it does
not exist, the overall target bitrate.
|
| nopt | | int nopt(Code) | | The number of optimized layers, or optimization points, without
counting the extra one coming from the overall target bitrate
|
| optbrate | | float optbrate(Code) | | The target bitrate to which specified layers should be optimized.
|
| totbrate | | float totbrate(Code) | | The overall target bitrate, for the whole bit stream
|
| totlyrs | | int totlyrs(Code) | | The total number of layers
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| LayersInfo | | public LayersInfo(float brate)(Code) | | Creates a new LayersInfo object. The overall target bitrate 'brate' is
always an extra optimization point, with no extra layers are after
it. Note that any optimization points that are added with addOptPoint()
are always added before the overall target bitrate.
Parameters:
brate - The overall target bitrate for the bit stream |
| addOptPoint | | public void addOptPoint(float brate, int elyrs)(Code) | | Adds a new optimization point, with target bitrate 'brate' and with
'elyrs' (unoptimized) extra layers after it. The target bitrate 'brate'
must be larger than the previous optimization point. The arguments are
checked and IllegalArgumentException is thrown if they are not correct.
Parameters:
brate - The target bitrate for the optimized layer.
Parameters:
elyrs - The number of extra (unoptimized) layers to add after theoptimized layer. |
| getExtraLayers | | public int getExtraLayers(int n)(Code) | | Returns the number of extra layers to add after the optimization point
'n', but before optimization point 'n+1'. If there is no optimization
point 'n+1' then they should be added before the overall target bitrate.
Parameters:
n - The optimization point index (starts at 0). The number of extra (unoptimized) layers to add after theoptimization point 'n' |
| getNOptPoints | | public int getNOptPoints()(Code) | | Returns the number of layers to optimize, or optimization points, as
specified by this object.
The number of optimization points |
| getTargetBitrate | | public float getTargetBitrate(int n)(Code) | | Returns the target bitrate of the optmimization point 'n'.
Parameters:
n - The optimization point index (starts at 0). The target bitrate (in bpp) for the optimization point 'n'. |
| getTotBitrate | | public float getTotBitrate()(Code) | | Returns the overall target bitrate for the entire bit stream.
The overall target bitrate |
| getTotNumLayers | | public int getTotNumLayers()(Code) | | Returns the total number of layers, according to the layer
specification of this object and the overall target bitrate.
The total number of layers, according to the layer spec. |
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