1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/images/SkImageDecoder.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,307 @@
1.4 +/*
1.5 + * Copyright 2006 The Android Open Source Project
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +
1.12 +#include "SkImageDecoder.h"
1.13 +#include "SkBitmap.h"
1.14 +#include "SkImagePriv.h"
1.15 +#include "SkPixelRef.h"
1.16 +#include "SkStream.h"
1.17 +#include "SkTemplates.h"
1.18 +#include "SkCanvas.h"
1.19 +
1.20 +static SkBitmap::Config gDeviceConfig = SkBitmap::kNo_Config;
1.21 +
1.22 +SkBitmap::Config SkImageDecoder::GetDeviceConfig()
1.23 +{
1.24 + return gDeviceConfig;
1.25 +}
1.26 +
1.27 +void SkImageDecoder::SetDeviceConfig(SkBitmap::Config config)
1.28 +{
1.29 + gDeviceConfig = config;
1.30 +}
1.31 +
1.32 +///////////////////////////////////////////////////////////////////////////////
1.33 +
1.34 +SkImageDecoder::SkImageDecoder()
1.35 + : fPeeker(NULL)
1.36 + , fChooser(NULL)
1.37 + , fAllocator(NULL)
1.38 + , fSampleSize(1)
1.39 + , fDefaultPref(SkBitmap::kNo_Config)
1.40 + , fDitherImage(true)
1.41 + , fUsePrefTable(false)
1.42 + , fSkipWritingZeroes(false)
1.43 + , fPreferQualityOverSpeed(false)
1.44 + , fRequireUnpremultipliedColors(false) {
1.45 +}
1.46 +
1.47 +SkImageDecoder::~SkImageDecoder() {
1.48 + SkSafeUnref(fPeeker);
1.49 + SkSafeUnref(fChooser);
1.50 + SkSafeUnref(fAllocator);
1.51 +}
1.52 +
1.53 +void SkImageDecoder::copyFieldsToOther(SkImageDecoder* other) {
1.54 + if (NULL == other) {
1.55 + return;
1.56 + }
1.57 + other->setPeeker(fPeeker);
1.58 + other->setChooser(fChooser);
1.59 + other->setAllocator(fAllocator);
1.60 + other->setSampleSize(fSampleSize);
1.61 + if (fUsePrefTable) {
1.62 + other->setPrefConfigTable(fPrefTable);
1.63 + } else {
1.64 + other->fDefaultPref = fDefaultPref;
1.65 + }
1.66 + other->setDitherImage(fDitherImage);
1.67 + other->setSkipWritingZeroes(fSkipWritingZeroes);
1.68 + other->setPreferQualityOverSpeed(fPreferQualityOverSpeed);
1.69 + other->setRequireUnpremultipliedColors(fRequireUnpremultipliedColors);
1.70 +}
1.71 +
1.72 +SkImageDecoder::Format SkImageDecoder::getFormat() const {
1.73 + return kUnknown_Format;
1.74 +}
1.75 +
1.76 +const char* SkImageDecoder::getFormatName() const {
1.77 + return GetFormatName(this->getFormat());
1.78 +}
1.79 +
1.80 +const char* SkImageDecoder::GetFormatName(Format format) {
1.81 + switch (format) {
1.82 + case kUnknown_Format:
1.83 + return "Unknown Format";
1.84 + case kBMP_Format:
1.85 + return "BMP";
1.86 + case kGIF_Format:
1.87 + return "GIF";
1.88 + case kICO_Format:
1.89 + return "ICO";
1.90 + case kJPEG_Format:
1.91 + return "JPEG";
1.92 + case kPNG_Format:
1.93 + return "PNG";
1.94 + case kWBMP_Format:
1.95 + return "WBMP";
1.96 + case kWEBP_Format:
1.97 + return "WEBP";
1.98 + default:
1.99 + SkDEBUGFAIL("Invalid format type!");
1.100 + }
1.101 + return "Unknown Format";
1.102 +}
1.103 +
1.104 +SkImageDecoder::Peeker* SkImageDecoder::setPeeker(Peeker* peeker) {
1.105 + SkRefCnt_SafeAssign(fPeeker, peeker);
1.106 + return peeker;
1.107 +}
1.108 +
1.109 +SkImageDecoder::Chooser* SkImageDecoder::setChooser(Chooser* chooser) {
1.110 + SkRefCnt_SafeAssign(fChooser, chooser);
1.111 + return chooser;
1.112 +}
1.113 +
1.114 +SkBitmap::Allocator* SkImageDecoder::setAllocator(SkBitmap::Allocator* alloc) {
1.115 + SkRefCnt_SafeAssign(fAllocator, alloc);
1.116 + return alloc;
1.117 +}
1.118 +
1.119 +void SkImageDecoder::setSampleSize(int size) {
1.120 + if (size < 1) {
1.121 + size = 1;
1.122 + }
1.123 + fSampleSize = size;
1.124 +}
1.125 +
1.126 +bool SkImageDecoder::chooseFromOneChoice(SkBitmap::Config config, int width,
1.127 + int height) const {
1.128 + Chooser* chooser = fChooser;
1.129 +
1.130 + if (NULL == chooser) { // no chooser, we just say YES to decoding :)
1.131 + return true;
1.132 + }
1.133 + chooser->begin(1);
1.134 + chooser->inspect(0, config, width, height);
1.135 + return chooser->choose() == 0;
1.136 +}
1.137 +
1.138 +bool SkImageDecoder::allocPixelRef(SkBitmap* bitmap,
1.139 + SkColorTable* ctable) const {
1.140 + return bitmap->allocPixels(fAllocator, ctable);
1.141 +}
1.142 +
1.143 +///////////////////////////////////////////////////////////////////////////////
1.144 +
1.145 +void SkImageDecoder::setPrefConfigTable(const PrefConfigTable& prefTable) {
1.146 + fUsePrefTable = true;
1.147 + fPrefTable = prefTable;
1.148 +}
1.149 +
1.150 +SkBitmap::Config SkImageDecoder::getPrefConfig(SrcDepth srcDepth,
1.151 + bool srcHasAlpha) const {
1.152 + SkBitmap::Config config = SkBitmap::kNo_Config;
1.153 +
1.154 + if (fUsePrefTable) {
1.155 + switch (srcDepth) {
1.156 + case kIndex_SrcDepth:
1.157 + config = srcHasAlpha ? fPrefTable.fPrefFor_8Index_YesAlpha_src
1.158 + : fPrefTable.fPrefFor_8Index_NoAlpha_src;
1.159 + break;
1.160 + case k8BitGray_SrcDepth:
1.161 + config = fPrefTable.fPrefFor_8Gray_src;
1.162 + break;
1.163 + case k32Bit_SrcDepth:
1.164 + config = srcHasAlpha ? fPrefTable.fPrefFor_8bpc_YesAlpha_src
1.165 + : fPrefTable.fPrefFor_8bpc_NoAlpha_src;
1.166 + break;
1.167 + }
1.168 + } else {
1.169 + config = fDefaultPref;
1.170 + }
1.171 +
1.172 + if (SkBitmap::kNo_Config == config) {
1.173 + config = SkImageDecoder::GetDeviceConfig();
1.174 + }
1.175 + return config;
1.176 +}
1.177 +
1.178 +bool SkImageDecoder::decode(SkStream* stream, SkBitmap* bm,
1.179 + SkBitmap::Config pref, Mode mode) {
1.180 + // we reset this to false before calling onDecode
1.181 + fShouldCancelDecode = false;
1.182 + // assign this, for use by getPrefConfig(), in case fUsePrefTable is false
1.183 + fDefaultPref = pref;
1.184 +
1.185 + // pass a temporary bitmap, so that if we return false, we are assured of
1.186 + // leaving the caller's bitmap untouched.
1.187 + SkBitmap tmp;
1.188 + if (!this->onDecode(stream, &tmp, mode)) {
1.189 + return false;
1.190 + }
1.191 + bm->swap(tmp);
1.192 + return true;
1.193 +}
1.194 +
1.195 +bool SkImageDecoder::decodeSubset(SkBitmap* bm, const SkIRect& rect,
1.196 + SkBitmap::Config pref) {
1.197 + // we reset this to false before calling onDecodeSubset
1.198 + fShouldCancelDecode = false;
1.199 + // assign this, for use by getPrefConfig(), in case fUsePrefTable is false
1.200 + fDefaultPref = pref;
1.201 +
1.202 + return this->onDecodeSubset(bm, rect);
1.203 +}
1.204 +
1.205 +bool SkImageDecoder::buildTileIndex(SkStreamRewindable* stream,
1.206 + int *width, int *height) {
1.207 + // we reset this to false before calling onBuildTileIndex
1.208 + fShouldCancelDecode = false;
1.209 +
1.210 + return this->onBuildTileIndex(stream, width, height);
1.211 +}
1.212 +
1.213 +bool SkImageDecoder::cropBitmap(SkBitmap *dst, SkBitmap *src, int sampleSize,
1.214 + int dstX, int dstY, int width, int height,
1.215 + int srcX, int srcY) {
1.216 + int w = width / sampleSize;
1.217 + int h = height / sampleSize;
1.218 + if (src->config() == SkBitmap::kIndex8_Config) {
1.219 + // kIndex8 does not allow drawing via an SkCanvas, as is done below.
1.220 + // Instead, use extractSubset. Note that this shares the SkPixelRef and
1.221 + // SkColorTable.
1.222 + // FIXME: Since src is discarded in practice, this holds on to more
1.223 + // pixels than is strictly necessary. Switch to a copy if memory
1.224 + // savings are more important than speed here. This also means
1.225 + // that the pixels in dst can not be reused (though there is no
1.226 + // allocation, which was already done on src).
1.227 + int x = (dstX - srcX) / sampleSize;
1.228 + int y = (dstY - srcY) / sampleSize;
1.229 + SkIRect subset = SkIRect::MakeXYWH(x, y, w, h);
1.230 + return src->extractSubset(dst, subset);
1.231 + }
1.232 + // if the destination has no pixels then we must allocate them.
1.233 + if (dst->isNull()) {
1.234 + dst->setConfig(src->config(), w, h, 0, src->alphaType());
1.235 +
1.236 + if (!this->allocPixelRef(dst, NULL)) {
1.237 + SkDEBUGF(("failed to allocate pixels needed to crop the bitmap"));
1.238 + return false;
1.239 + }
1.240 + }
1.241 + // check to see if the destination is large enough to decode the desired
1.242 + // region. If this assert fails we will just draw as much of the source
1.243 + // into the destination that we can.
1.244 + if (dst->width() < w || dst->height() < h) {
1.245 + SkDEBUGF(("SkImageDecoder::cropBitmap does not have a large enough bitmap.\n"));
1.246 + }
1.247 +
1.248 + // Set the Src_Mode for the paint to prevent transparency issue in the
1.249 + // dest in the event that the dest was being re-used.
1.250 + SkPaint paint;
1.251 + paint.setXfermodeMode(SkXfermode::kSrc_Mode);
1.252 +
1.253 + SkCanvas canvas(*dst);
1.254 + canvas.drawSprite(*src, (srcX - dstX) / sampleSize,
1.255 + (srcY - dstY) / sampleSize,
1.256 + &paint);
1.257 + return true;
1.258 +}
1.259 +
1.260 +///////////////////////////////////////////////////////////////////////////////
1.261 +
1.262 +bool SkImageDecoder::DecodeFile(const char file[], SkBitmap* bm,
1.263 + SkBitmap::Config pref, Mode mode, Format* format) {
1.264 + SkASSERT(file);
1.265 + SkASSERT(bm);
1.266 +
1.267 + SkAutoTUnref<SkStreamRewindable> stream(SkStream::NewFromFile(file));
1.268 + if (stream.get()) {
1.269 + if (SkImageDecoder::DecodeStream(stream, bm, pref, mode, format)) {
1.270 + bm->pixelRef()->setURI(file);
1.271 + return true;
1.272 + }
1.273 + }
1.274 + return false;
1.275 +}
1.276 +
1.277 +bool SkImageDecoder::DecodeMemory(const void* buffer, size_t size, SkBitmap* bm,
1.278 + SkBitmap::Config pref, Mode mode, Format* format) {
1.279 + if (0 == size) {
1.280 + return false;
1.281 + }
1.282 + SkASSERT(buffer);
1.283 +
1.284 + SkMemoryStream stream(buffer, size);
1.285 + return SkImageDecoder::DecodeStream(&stream, bm, pref, mode, format);
1.286 +}
1.287 +
1.288 +bool SkImageDecoder::DecodeStream(SkStreamRewindable* stream, SkBitmap* bm,
1.289 + SkBitmap::Config pref, Mode mode,
1.290 + Format* format) {
1.291 + SkASSERT(stream);
1.292 + SkASSERT(bm);
1.293 +
1.294 + bool success = false;
1.295 + SkImageDecoder* codec = SkImageDecoder::Factory(stream);
1.296 +
1.297 + if (NULL != codec) {
1.298 + success = codec->decode(stream, bm, pref, mode);
1.299 + if (success && format) {
1.300 + *format = codec->getFormat();
1.301 + if (kUnknown_Format == *format) {
1.302 + if (stream->rewind()) {
1.303 + *format = GetStreamFormat(stream);
1.304 + }
1.305 + }
1.306 + }
1.307 + delete codec;
1.308 + }
1.309 + return success;
1.310 +}
