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|
/*
* Copyright 2015 The Etc2Comp Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
EtcImage.cpp
Image is an array of 4x4 blocks that represent the encoding of the source image
*/
#include "EtcConfig.h"
#include <stdlib.h>
#include "EtcImage.h"
#include "Etc.h"
#include "EtcBlock4x4.h"
#include "EtcBlock4x4EncodingBits.h"
#include "EtcSortedBlockList.h"
#if ETC_WINDOWS
#include <windows.h>
#endif
#include <ctime>
#include <chrono>
#include <future>
#include <stdio.h>
#include <string.h>
#include <assert.h>
// fix conflict with Block4x4::AlphaMix
#ifdef OPAQUE
#undef OPAQUE
#endif
#ifdef TRANSPARENT
#undef TRANSPARENT
#endif
namespace Etc
{
// ----------------------------------------------------------------------------------------------------
//
Image::Image(void)
{
m_encodingStatus = EncodingStatus::SUCCESS;
m_warningsToCapture = EncodingStatus::SUCCESS;
m_pafrgbaSource = nullptr;
m_pablock = nullptr;
m_encodingbitsformat = Block4x4EncodingBits::Format::UNKNOWN;
m_uiEncodingBitsBytes = 0;
m_paucEncodingBits = nullptr;
m_format = Format::UNKNOWN;
m_iNumOpaquePixels = 0;
m_iNumTranslucentPixels = 0;
m_iNumTransparentPixels = 0;
}
// ----------------------------------------------------------------------------------------------------
// constructor using source image
// used to set state before Encode() is called
//
Image::Image(float *a_pafSourceRGBA, unsigned int a_uiSourceWidth,
unsigned int a_uiSourceHeight,
ErrorMetric a_errormetric)
{
m_encodingStatus = EncodingStatus::SUCCESS;
m_warningsToCapture = EncodingStatus::SUCCESS;
m_pafrgbaSource = (ColorFloatRGBA *) a_pafSourceRGBA;
m_uiSourceWidth = a_uiSourceWidth;
m_uiSourceHeight = a_uiSourceHeight;
m_uiExtendedWidth = CalcExtendedDimension((unsigned short)m_uiSourceWidth);
m_uiExtendedHeight = CalcExtendedDimension((unsigned short)m_uiSourceHeight);
m_uiBlockColumns = m_uiExtendedWidth >> 2;
m_uiBlockRows = m_uiExtendedHeight >> 2;
m_pablock = new Block4x4[GetNumberOfBlocks()];
assert(m_pablock);
m_format = Format::UNKNOWN;
m_encodingbitsformat = Block4x4EncodingBits::Format::UNKNOWN;
m_uiEncodingBitsBytes = 0;
m_paucEncodingBits = nullptr;
m_errormetric = a_errormetric;
m_fEffort = 0.0f;
m_iEncodeTime_ms = -1;
m_iNumOpaquePixels = 0;
m_iNumTranslucentPixels = 0;
m_iNumTransparentPixels = 0;
m_bVerboseOutput = false;
}
// ----------------------------------------------------------------------------------------------------
// constructor using encoding bits
// recreates encoding state using a previously encoded image
//
Image::Image(Format a_format,
unsigned int a_uiSourceWidth, unsigned int a_uiSourceHeight,
unsigned char *a_paucEncidingBits, unsigned int a_uiEncodingBitsBytes,
Image *a_pimageSource, ErrorMetric a_errormetric)
{
m_encodingStatus = EncodingStatus::SUCCESS;
m_pafrgbaSource = nullptr;
m_uiSourceWidth = a_uiSourceWidth;
m_uiSourceHeight = a_uiSourceHeight;
m_uiExtendedWidth = CalcExtendedDimension((unsigned short)m_uiSourceWidth);
m_uiExtendedHeight = CalcExtendedDimension((unsigned short)m_uiSourceHeight);
m_uiBlockColumns = m_uiExtendedWidth >> 2;
m_uiBlockRows = m_uiExtendedHeight >> 2;
unsigned int uiBlocks = GetNumberOfBlocks();
m_pablock = new Block4x4[uiBlocks];
assert(m_pablock);
m_format = a_format;
m_iNumOpaquePixels = 0;
m_iNumTranslucentPixels = 0;
m_iNumTransparentPixels = 0;
m_encodingbitsformat = DetermineEncodingBitsFormat(m_format);
if (m_encodingbitsformat == Block4x4EncodingBits::Format::UNKNOWN)
{
AddToEncodingStatus(ERROR_UNKNOWN_FORMAT);
return;
}
m_uiEncodingBitsBytes = a_uiEncodingBitsBytes;
m_paucEncodingBits = a_paucEncidingBits;
m_errormetric = a_errormetric;
m_fEffort = 0.0f;
m_bVerboseOutput = false;
m_iEncodeTime_ms = -1;
unsigned char *paucEncodingBits = m_paucEncodingBits;
unsigned int uiEncodingBitsBytesPerBlock = Block4x4EncodingBits::GetBytesPerBlock(m_encodingbitsformat);
unsigned int uiH = 0;
unsigned int uiV = 0;
for (unsigned int uiBlock = 0; uiBlock < uiBlocks; uiBlock++)
{
m_pablock[uiBlock].InitFromEtcEncodingBits(a_format, uiH, uiV, paucEncodingBits,
a_pimageSource, a_errormetric);
paucEncodingBits += uiEncodingBitsBytesPerBlock;
uiH += 4;
if (uiH >= m_uiSourceWidth)
{
uiH = 0;
uiV += 4;
}
}
}
// ----------------------------------------------------------------------------------------------------
//
Image::~Image(void)
{
if (m_pablock != nullptr)
{
delete[] m_pablock;
m_pablock = nullptr;
}
/*if (m_paucEncodingBits != nullptr)
{
delete[] m_paucEncodingBits;
m_paucEncodingBits = nullptr;
}*/
}
// ----------------------------------------------------------------------------------------------------
// encode an image
// create a set of encoding bits that conforms to a_format
// find best fit using a_errormetric
// explore a range of possible encodings based on a_fEffort (range = [0:100])
// speed up process using a_uiJobs as the number of process threads (a_uiJobs must not excede a_uiMaxJobs)
//
Image::EncodingStatus Image::Encode(Format a_format, ErrorMetric a_errormetric, float a_fEffort, unsigned int a_uiJobs, unsigned int a_uiMaxJobs)
{
auto start = std::chrono::steady_clock::now();
m_encodingStatus = EncodingStatus::SUCCESS;
m_format = a_format;
m_errormetric = a_errormetric;
m_fEffort = a_fEffort;
if (m_errormetric < 0 || m_errormetric > ERROR_METRICS)
{
AddToEncodingStatus(ERROR_UNKNOWN_ERROR_METRIC);
return m_encodingStatus;
}
if (m_fEffort < ETCCOMP_MIN_EFFORT_LEVEL)
{
AddToEncodingStatus(WARNING_EFFORT_OUT_OF_RANGE);
m_fEffort = ETCCOMP_MIN_EFFORT_LEVEL;
}
else if (m_fEffort > ETCCOMP_MAX_EFFORT_LEVEL)
{
AddToEncodingStatus(WARNING_EFFORT_OUT_OF_RANGE);
m_fEffort = ETCCOMP_MAX_EFFORT_LEVEL;
}
if (a_uiJobs < 1)
{
a_uiJobs = 1;
AddToEncodingStatus(WARNING_JOBS_OUT_OF_RANGE);
}
else if (a_uiJobs > a_uiMaxJobs)
{
a_uiJobs = a_uiMaxJobs;
AddToEncodingStatus(WARNING_JOBS_OUT_OF_RANGE);
}
m_encodingbitsformat = DetermineEncodingBitsFormat(m_format);
if (m_encodingbitsformat == Block4x4EncodingBits::Format::UNKNOWN)
{
AddToEncodingStatus(ERROR_UNKNOWN_FORMAT);
return m_encodingStatus;
}
assert(m_paucEncodingBits == nullptr);
m_uiEncodingBitsBytes = GetNumberOfBlocks() * Block4x4EncodingBits::GetBytesPerBlock(m_encodingbitsformat);
m_paucEncodingBits = new unsigned char[m_uiEncodingBitsBytes];
InitBlocksAndBlockSorter();
std::future<void> *handle = new std::future<void>[a_uiMaxJobs];
unsigned int uiNumThreadsNeeded = 0;
unsigned int uiUnfinishedBlocks = GetNumberOfBlocks();
uiNumThreadsNeeded = (uiUnfinishedBlocks < a_uiJobs) ? uiUnfinishedBlocks : a_uiJobs;
for (int i = 0; i < (int)uiNumThreadsNeeded - 1; i++)
{
handle[i] = async(std::launch::async, &Image::RunFirstPass, this, i, uiNumThreadsNeeded);
}
RunFirstPass(uiNumThreadsNeeded - 1, uiNumThreadsNeeded);
for (int i = 0; i < (int)uiNumThreadsNeeded - 1; i++)
{
handle[i].get();
}
// perform effort-based encoding
if (m_fEffort > ETCCOMP_MIN_EFFORT_LEVEL)
{
unsigned int uiFinishedBlocks = 0;
unsigned int uiTotalEffortBlocks = static_cast<unsigned int>(roundf(0.01f * m_fEffort * GetNumberOfBlocks()));
if (m_bVerboseOutput)
{
printf("effortblocks = %d\n", uiTotalEffortBlocks);
}
unsigned int uiPass = 0;
while (1)
{
if (m_bVerboseOutput)
{
uiPass++;
printf("pass %u\n", uiPass);
}
m_psortedblocklist->Sort();
uiUnfinishedBlocks = m_psortedblocklist->GetNumberOfSortedBlocks();
uiFinishedBlocks = GetNumberOfBlocks() - uiUnfinishedBlocks;
if (m_bVerboseOutput)
{
printf(" %u unfinished blocks\n", uiUnfinishedBlocks);
// m_psortedblocklist->Print();
}
//stop enocding when we did enough to satify the effort percentage
if (uiFinishedBlocks >= uiTotalEffortBlocks)
{
if (m_bVerboseOutput)
{
printf("Finished %d Blocks out of %d\n", uiFinishedBlocks, uiTotalEffortBlocks);
}
break;
}
unsigned int uiIteratedBlocks = 0;
unsigned int blocksToIterateThisPass = (uiTotalEffortBlocks - uiFinishedBlocks);
uiNumThreadsNeeded = (uiUnfinishedBlocks < a_uiJobs) ? uiUnfinishedBlocks : a_uiJobs;
if (uiNumThreadsNeeded <= 1)
{
//since we already how many blocks each thread will process
//cap the thread limit to do the proper amount of work, and not more
uiIteratedBlocks = IterateThroughWorstBlocks(blocksToIterateThisPass, 0, 1);
}
else
{
//we have a lot of work to do, so lets multi thread it
std::future<unsigned int> *handleToBlockEncoders = new std::future<unsigned int>[uiNumThreadsNeeded-1];
for (int i = 0; i < (int)uiNumThreadsNeeded - 1; i++)
{
handleToBlockEncoders[i] = async(std::launch::async, &Image::IterateThroughWorstBlocks, this, blocksToIterateThisPass, i, uiNumThreadsNeeded);
}
uiIteratedBlocks = IterateThroughWorstBlocks(blocksToIterateThisPass, uiNumThreadsNeeded - 1, uiNumThreadsNeeded);
for (int i = 0; i < (int)uiNumThreadsNeeded - 1; i++)
{
uiIteratedBlocks += handleToBlockEncoders[i].get();
}
delete[] handleToBlockEncoders;
}
if (m_bVerboseOutput)
{
printf(" %u iterated blocks\n", uiIteratedBlocks);
}
}
}
// generate Etc2-compatible bit-format 4x4 blocks
for (int i = 0; i < (int)a_uiJobs - 1; i++)
{
handle[i] = async(std::launch::async, &Image::SetEncodingBits, this, i, a_uiJobs);
}
SetEncodingBits(a_uiJobs - 1, a_uiJobs);
for (int i = 0; i < (int)a_uiJobs - 1; i++)
{
handle[i].get();
}
auto end = std::chrono::steady_clock::now();
std::chrono::milliseconds elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(end - start);
m_iEncodeTime_ms = (int)elapsed.count();
delete[] handle;
delete m_psortedblocklist;
return m_encodingStatus;
}
// ----------------------------------------------------------------------------------------------------
// iterate the encoding thru the blocks with the worst error
// stop when a_uiMaxBlocks blocks have been iterated
// split the blocks between the process threads using a_uiMultithreadingOffset and a_uiMultithreadingStride
//
unsigned int Image::IterateThroughWorstBlocks(unsigned int a_uiMaxBlocks,
unsigned int a_uiMultithreadingOffset,
unsigned int a_uiMultithreadingStride)
{
assert(a_uiMultithreadingStride > 0);
unsigned int uiIteratedBlocks = a_uiMultithreadingOffset;
SortedBlockList::Link *plink = m_psortedblocklist->GetLinkToFirstBlock();
for (plink = plink->Advance(a_uiMultithreadingOffset);
plink != nullptr;
plink = plink->Advance(a_uiMultithreadingStride) )
{
if (uiIteratedBlocks >= a_uiMaxBlocks)
{
break;
}
plink->GetBlock()->PerformEncodingIteration(m_fEffort);
uiIteratedBlocks += a_uiMultithreadingStride;
}
return uiIteratedBlocks;
}
// ----------------------------------------------------------------------------------------------------
// determine which warnings to check for during Encode() based on encoding format
//
void Image::FindEncodingWarningTypesForCurFormat()
{
TrackEncodingWarning(WARNING_ALL_TRANSPARENT_PIXELS);
TrackEncodingWarning(WARNING_SOME_RGBA_NOT_0_TO_1);
switch (m_format)
{
case Image::Format::ETC1:
case Image::Format::RGB8:
case Image::Format::SRGB8:
TrackEncodingWarning(WARNING_SOME_NON_OPAQUE_PIXELS);
TrackEncodingWarning(WARNING_SOME_TRANSLUCENT_PIXELS);
break;
case Image::Format::RGB8A1:
case Image::Format::SRGB8A1:
TrackEncodingWarning(WARNING_SOME_TRANSLUCENT_PIXELS);
TrackEncodingWarning(WARNING_ALL_OPAQUE_PIXELS);
break;
case Image::Format::RGBA8:
case Image::Format::SRGBA8:
TrackEncodingWarning(WARNING_ALL_OPAQUE_PIXELS);
break;
case Image::Format::R11:
case Image::Format::SIGNED_R11:
TrackEncodingWarning(WARNING_SOME_NON_OPAQUE_PIXELS);
TrackEncodingWarning(WARNING_SOME_TRANSLUCENT_PIXELS);
TrackEncodingWarning(WARNING_SOME_GREEN_VALUES_ARE_NOT_ZERO);
TrackEncodingWarning(WARNING_SOME_BLUE_VALUES_ARE_NOT_ZERO);
break;
case Image::Format::RG11:
case Image::Format::SIGNED_RG11:
TrackEncodingWarning(WARNING_SOME_NON_OPAQUE_PIXELS);
TrackEncodingWarning(WARNING_SOME_TRANSLUCENT_PIXELS);
TrackEncodingWarning(WARNING_SOME_BLUE_VALUES_ARE_NOT_ZERO);
break;
case Image::Format::FORMATS:
case Image::Format::UNKNOWN:
default:
assert(0);
break;
}
}
// ----------------------------------------------------------------------------------------------------
// examine source pixels to check for warnings
//
void Image::FindAndSetEncodingWarnings()
{
int numPixels = (m_uiBlockRows * 4) * (m_uiBlockColumns * 4);
if (m_iNumOpaquePixels == numPixels)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_ALL_OPAQUE_PIXELS);
}
if (m_iNumOpaquePixels < numPixels)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_NON_OPAQUE_PIXELS);
}
if (m_iNumTranslucentPixels > 0)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_TRANSLUCENT_PIXELS);
}
if (m_iNumTransparentPixels == numPixels)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_ALL_TRANSPARENT_PIXELS);
}
if (m_numColorValues.fB > 0.0f)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_BLUE_VALUES_ARE_NOT_ZERO);
}
if (m_numColorValues.fG > 0.0f)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_GREEN_VALUES_ARE_NOT_ZERO);
}
if (m_numOutOfRangeValues.fR > 0.0f || m_numOutOfRangeValues.fG > 0.0f)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_RGBA_NOT_0_TO_1);
}
if (m_numOutOfRangeValues.fB > 0.0f || m_numOutOfRangeValues.fA > 0.0f)
{
AddToEncodingStatusIfSignfigant(Image::EncodingStatus::WARNING_SOME_RGBA_NOT_0_TO_1);
}
}
// ----------------------------------------------------------------------------------------------------
// return a string name for a given image format
//
const char * Image::EncodingFormatToString(Image::Format a_format)
{
switch (a_format)
{
case Image::Format::ETC1:
return "ETC1";
case Image::Format::RGB8:
return "RGB8";
case Image::Format::SRGB8:
return "SRGB8";
case Image::Format::RGB8A1:
return "RGB8A1";
case Image::Format::SRGB8A1:
return "SRGB8A1";
case Image::Format::RGBA8:
return "RGBA8";
case Image::Format::SRGBA8:
return "SRGBA8";
case Image::Format::R11:
return "R11";
case Image::Format::SIGNED_R11:
return "SIGNED_R11";
case Image::Format::RG11:
return "RG11";
case Image::Format::SIGNED_RG11:
return "SIGNED_RG11";
case Image::Format::FORMATS:
case Image::Format::UNKNOWN:
default:
return "UNKNOWN";
}
}
// ----------------------------------------------------------------------------------------------------
// return a string name for the image's format
//
const char * Image::EncodingFormatToString(void)
{
return EncodingFormatToString(m_format);
}
// ----------------------------------------------------------------------------------------------------
// init image blocks prior to encoding
// init block sorter for subsequent sortings
// check for encoding warnings
//
void Image::InitBlocksAndBlockSorter(void)
{
FindEncodingWarningTypesForCurFormat();
// init each block
Block4x4 *pblock = m_pablock;
unsigned char *paucEncodingBits = m_paucEncodingBits;
for (unsigned int uiBlockRow = 0; uiBlockRow < m_uiBlockRows; uiBlockRow++)
{
unsigned int uiBlockV = uiBlockRow * 4;
for (unsigned int uiBlockColumn = 0; uiBlockColumn < m_uiBlockColumns; uiBlockColumn++)
{
unsigned int uiBlockH = uiBlockColumn * 4;
pblock->InitFromSource(this, uiBlockH, uiBlockV, paucEncodingBits, m_errormetric);
paucEncodingBits += Block4x4EncodingBits::GetBytesPerBlock(m_encodingbitsformat);
pblock++;
}
}
FindAndSetEncodingWarnings();
// init block sorter
{
m_psortedblocklist = new SortedBlockList(GetNumberOfBlocks(), 100);
for (unsigned int uiBlock = 0; uiBlock < GetNumberOfBlocks(); uiBlock++)
{
pblock = &m_pablock[uiBlock];
m_psortedblocklist->AddBlock(pblock);
}
}
}
// ----------------------------------------------------------------------------------------------------
// run the first pass of the encoder
// the encoder generally finds a reasonable, fast encoding
// this is run on all blocks regardless of effort to ensure that all blocks have a valid encoding
//
void Image::RunFirstPass(unsigned int a_uiMultithreadingOffset, unsigned int a_uiMultithreadingStride)
{
assert(a_uiMultithreadingStride > 0);
for (unsigned int uiBlock = a_uiMultithreadingOffset;
uiBlock < GetNumberOfBlocks();
uiBlock += a_uiMultithreadingStride)
{
Block4x4 *pblock = &m_pablock[uiBlock];
pblock->PerformEncodingIteration(m_fEffort);
}
}
// ----------------------------------------------------------------------------------------------------
// set the encoding bits (for the output file) based on the best encoding for each block
//
void Image::SetEncodingBits(unsigned int a_uiMultithreadingOffset,
unsigned int a_uiMultithreadingStride)
{
assert(a_uiMultithreadingStride > 0);
for (unsigned int uiBlock = a_uiMultithreadingOffset;
uiBlock < GetNumberOfBlocks();
uiBlock += a_uiMultithreadingStride)
{
Block4x4 *pblock = &m_pablock[uiBlock];
pblock->SetEncodingBitsFromEncoding();
}
}
// ----------------------------------------------------------------------------------------------------
// return the image error
// image error is the sum of all block errors
//
float Image::GetError(void)
{
float fError = 0.0f;
for (unsigned int uiBlock = 0; uiBlock < GetNumberOfBlocks(); uiBlock++)
{
Block4x4 *pblock = &m_pablock[uiBlock];
fError += pblock->GetError();
}
return fError;
}
// ----------------------------------------------------------------------------------------------------
// determine the encoding bits format based on the encoding format
// the encoding bits format is a family of bit encodings that are shared across various encoding formats
//
Block4x4EncodingBits::Format Image::DetermineEncodingBitsFormat(Format a_format)
{
Block4x4EncodingBits::Format encodingbitsformat;
// determine encoding bits format from image format
switch (a_format)
{
case Format::ETC1:
case Format::RGB8:
case Format::SRGB8:
encodingbitsformat = Block4x4EncodingBits::Format::RGB8;
break;
case Format::RGBA8:
case Format::SRGBA8:
encodingbitsformat = Block4x4EncodingBits::Format::RGBA8;
break;
case Format::R11:
case Format::SIGNED_R11:
encodingbitsformat = Block4x4EncodingBits::Format::R11;
break;
case Format::RG11:
case Format::SIGNED_RG11:
encodingbitsformat = Block4x4EncodingBits::Format::RG11;
break;
case Format::RGB8A1:
case Format::SRGB8A1:
encodingbitsformat = Block4x4EncodingBits::Format::RGB8A1;
break;
default:
encodingbitsformat = Block4x4EncodingBits::Format::UNKNOWN;
break;
}
return encodingbitsformat;
}
// ----------------------------------------------------------------------------------------------------
//
} // namespace Etc
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