1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128
|
/*************************************************************************
This project implements a complete(!) JPEG (Recommendation ITU-T
T.81 | ISO/IEC 10918-1) codec, plus a library that can be used to
encode and decode JPEG streams.
It also implements ISO/IEC 18477 aka JPEG XT which is an extension
towards intermediate, high-dynamic-range lossy and lossless coding
of JPEG. In specific, it supports ISO/IEC 18477-3/-6/-7/-8 encoding.
Note that only Profiles C and D of ISO/IEC 18477-7 are supported
here. Check the JPEG XT reference software for a full implementation
of ISO/IEC 18477-7.
Copyright (C) 2012-2018 Thomas Richter, University of Stuttgart and
Accusoft. (C) 2019-2020 Thomas Richter, Fraunhofer IIS.
This program is available under two licenses, GPLv3 and the ITU
Software licence Annex A Option 2, RAND conditions.
For the full text of the GPU license option, see README.license.gpl.
For the full text of the ITU license option, see README.license.itu.
You may freely select between these two options.
For the GPL option, please note the following:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*************************************************************************/
/*
** This box defines the output process, namely whether data is casted
** to float, whether a nonlinearity is applied, whether the data is
** clamped and several other options required as last processing
** step of the output conversion.
**
** It is a subbox of the merging specification box.
**
** $Id: outputconversionbox.cpp,v 1.3 2014/09/30 08:33:15 thor Exp $
**
*/
/// Includes
#include "boxes/box.hpp"
#include "boxes/outputconversionbox.hpp"
#include "io/bytestream.hpp"
#include "io/memorystream.hpp"
///
/// OutputConversionBox::CreateBoxContent
// Create the contents of the box. The size
// is computed automatically by the superbox.
bool OutputConversionBox::CreateBoxContent(class MemoryStream *target)
{
UBYTE v;
v = m_ucExtraRangeBits << 4;
if (m_bLossless)
v |= 0x08;
if (m_bCastToFloat)
v |= 0x04;
if (m_bEnableClamping)
v |= 0x02;
if (m_bEnableLookup)
v |= 0x01;
target->Put(v);
if (m_bEnableLookup) {
target->Put((m_ucOutputLookup[0] << 4) | (m_ucOutputLookup[1]));
target->Put((m_ucOutputLookup[2] << 4) | (m_ucOutputLookup[3]));
} else {
target->Put(0);
target->Put(0);
}
return true;
}
///
/// OutputConversionBox::ParseBoxContent
// Read the contents of this box and place it in the fields.
bool OutputConversionBox::ParseBoxContent(class ByteStream *stream,UQUAD boxsize)
{
UBYTE v;
if (boxsize != 3)
JPG_THROW(MALFORMED_STREAM,"OutputConversionBox::ParseBoxContent","Malformed JPEG stream, "
"Output Conversion box size is invalid");
v = stream->Get();
m_ucExtraRangeBits = v >> 4;
if (m_ucExtraRangeBits > 8)
JPG_THROW(MALFORMED_STREAM,"OutputConversionBox::ParseBoxContent","Malformed JPEG stream, "
"bit depths cannot be larger than 16");
m_bLossless = (v & 0x08)?true:false;
m_bCastToFloat = (v & 0x04)?true:false;
m_bEnableClamping = (v & 0x02)?true:false;
m_bEnableLookup = (v & 0x01)?true:false;
if (m_bEnableLookup) {
v = stream->Get();
m_ucOutputLookup[0] = v >> 4;
m_ucOutputLookup[1] = v & 0x0f;
v = stream->Get();
m_ucOutputLookup[2] = v >> 4;
m_ucOutputLookup[3] = v & 0x0f;
} else {
if (stream->GetWord() != 0)
JPG_THROW(MALFORMED_STREAM,"OutputConversionBox::ParseBoxContent","Malformed JPEG stream, "
"output conversion is disabled, but lookup information is not zero");
}
return true;
}
///
|