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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #include "jpeg_reader.h"
     18 #include "error_codes.h"
     19 #include "jpeg_hook.h"
     20 
     21 #include <setjmp.h>
     22 
     23 JpegReader::JpegReader() :
     24                 mInfo(),
     25                 mErrorManager(),
     26                 mScanlineBuf(NULL),
     27                 mScanlineIter(NULL),
     28                 mScanlineBuflen(0),
     29                 mScanlineUnformattedBuflen(0),
     30                 mScanlineBytesRemaining(0),
     31                 mFormat(),
     32                 mFinished(false),
     33                 mSetup(false) {}
     34 
     35 JpegReader::~JpegReader() {
     36     if (reset() != J_SUCCESS) {
     37         LOGE("Failed to destroy compress object, JpegReader may leak memory.");
     38     }
     39 }
     40 
     41 int32_t JpegReader::setup(JNIEnv *env, jobject in, int32_t* width, int32_t* height,
     42         Jpeg_Config::Format format) {
     43     if (mFinished || mSetup) {
     44         return J_ERROR_FATAL;
     45     }
     46     if (env->ExceptionCheck()) {
     47         return J_EXCEPTION;
     48     }
     49 
     50     // Setup error handler
     51     SetupErrMgr(reinterpret_cast<j_common_ptr>(&mInfo), &mErrorManager);
     52     // Set jump address for error handling
     53     if (setjmp(mErrorManager.setjmp_buf)) {
     54         return J_ERROR_FATAL;
     55     }
     56 
     57     // Call libjpeg setup
     58     jpeg_create_decompress(&mInfo);
     59 
     60     // Setup our data source object, this allocates java global references
     61     int32_t flags = MakeSrc(&mInfo, env, in);
     62     if (flags != J_SUCCESS) {
     63         LOGE("Failed to make source with error code: %d ", flags);
     64         return flags;
     65     }
     66 
     67     // Reads jpeg file header
     68     jpeg_read_header(&mInfo, TRUE);
     69     jpeg_calc_output_dimensions(&mInfo);
     70 
     71     const int components = (static_cast<int>(format) & 0xff);
     72 
     73     // Do setup for input format
     74     switch (components) {
     75     case 1:
     76         mInfo.out_color_space = JCS_GRAYSCALE;
     77         mScanlineUnformattedBuflen = mInfo.output_width;
     78         break;
     79     case 3:
     80     case 4:
     81         mScanlineUnformattedBuflen = mInfo.output_width * components;
     82         if (mInfo.jpeg_color_space == JCS_CMYK
     83                 || mInfo.jpeg_color_space == JCS_YCCK) {
     84             // Always use cmyk for output in a 4 channel jpeg.
     85             // libjpeg has a builtin cmyk->rgb decoder.
     86             mScanlineUnformattedBuflen = mInfo.output_width * 4;
     87             mInfo.out_color_space = JCS_CMYK;
     88         } else {
     89             mInfo.out_color_space = JCS_RGB;
     90         }
     91         break;
     92     default:
     93         return J_ERROR_BAD_ARGS;
     94     }
     95 
     96     mScanlineBuflen = mInfo.output_width * components;
     97     mScanlineBytesRemaining = mScanlineBuflen;
     98     mScanlineBuf = (JSAMPLE *) (mInfo.mem->alloc_small)(
     99             reinterpret_cast<j_common_ptr>(&mInfo), JPOOL_PERMANENT,
    100             mScanlineUnformattedBuflen * sizeof(JSAMPLE));
    101     mScanlineIter = mScanlineBuf;
    102     jpeg_start_decompress(&mInfo);
    103 
    104     // Output image dimensions
    105     if (width != NULL) {
    106         *width = mInfo.output_width;
    107     }
    108     if (height != NULL) {
    109         *height = mInfo.output_height;
    110     }
    111 
    112     mFormat = format;
    113     mSetup = true;
    114     return J_SUCCESS;
    115 }
    116 
    117 int32_t JpegReader::read(int8_t* bytes, int32_t offset, int32_t count) {
    118     if (!mSetup) {
    119         return J_ERROR_FATAL;
    120     }
    121     if (mFinished) {
    122         return J_DONE;
    123     }
    124     // Set jump address for error handling
    125     if (setjmp(mErrorManager.setjmp_buf)) {
    126         return J_ERROR_FATAL;
    127     }
    128     if (count <= 0) {
    129         return J_ERROR_BAD_ARGS;
    130     }
    131     int32_t total_length = count;
    132     while (mInfo.output_scanline < mInfo.output_height) {
    133         if (count < mScanlineBytesRemaining) {
    134             // read partial scanline and return
    135             if (bytes != NULL) {
    136                 // Treat NULL bytes as a skip
    137                 memcpy((void*) (bytes + offset), (void*) mScanlineIter,
    138                         count * sizeof(int8_t));
    139             }
    140             mScanlineBytesRemaining -= count;
    141             mScanlineIter += count;
    142             return total_length;
    143         } else if (count > 0) {
    144             // read full scanline
    145             if (bytes != NULL) {
    146                 // Treat NULL bytes as a skip
    147                 memcpy((void*) (bytes + offset), (void*) mScanlineIter,
    148                         mScanlineBytesRemaining * sizeof(int8_t));
    149                 bytes += mScanlineBytesRemaining;
    150             }
    151             count -= mScanlineBytesRemaining;
    152             mScanlineBytesRemaining = 0;
    153         }
    154         // Scanline buffer exhausted, read next scanline
    155         if (jpeg_read_scanlines(&mInfo, &mScanlineBuf, 1) != 1) {
    156             // Always read full scanline, no IO suspension
    157             return J_ERROR_FATAL;
    158         }
    159         // Do in-place pixel formatting
    160         formatPixels(static_cast<uint8_t*>(mScanlineBuf),
    161                 mScanlineUnformattedBuflen);
    162 
    163         // Reset iterators
    164         mScanlineIter = mScanlineBuf;
    165         mScanlineBytesRemaining = mScanlineBuflen;
    166     }
    167 
    168     // Read all of the scanlines
    169     jpeg_finish_decompress(&mInfo);
    170     mFinished = true;
    171     return total_length - count;
    172 }
    173 
    174 void JpegReader::updateEnv(JNIEnv *env) {
    175     UpdateSrcEnv(&mInfo, env);
    176 }
    177 
    178 // Does in-place pixel formatting
    179 void JpegReader::formatPixels(uint8_t* buf, int32_t len) {
    180     uint8_t *iter = buf;
    181 
    182     // Do cmyk->rgb conversion if necessary
    183     switch (mInfo.out_color_space) {
    184     case JCS_CMYK:
    185         // Convert CMYK to RGB
    186         int r, g, b, c, m, y, k;
    187         for (int i = 0; i < len; i += 4) {
    188             c = buf[i + 0];
    189             m = buf[i + 1];
    190             y = buf[i + 2];
    191             k = buf[i + 3];
    192             // Handle fmt for weird photoshop markers
    193             if (mInfo.saw_Adobe_marker) {
    194                 r = (k * c) / 255;
    195                 g = (k * m) / 255;
    196                 b = (k * y) / 255;
    197             } else {
    198                 r = (255 - k) * (255 - c) / 255;
    199                 g = (255 - k) * (255 - m) / 255;
    200                 b = (255 - k) * (255 - y) / 255;
    201             }
    202             *iter++ = r;
    203             *iter++ = g;
    204             *iter++ = b;
    205         }
    206         break;
    207     case JCS_RGB:
    208         iter += (len * 3 / 4);
    209         break;
    210     case JCS_GRAYSCALE:
    211     default:
    212         return;
    213     }
    214 
    215     // Do endianness and alpha for output format
    216     if (mFormat == Jpeg_Config::FORMAT_RGBA) {
    217         // Set alphas to 255
    218         uint8_t* end = buf + len - 1;
    219         for (int i = len - 1; i >= 0; i -= 4) {
    220             buf[i] = 255;
    221             buf[i - 1] = *--iter;
    222             buf[i - 2] = *--iter;
    223             buf[i - 3] = *--iter;
    224         }
    225     } else if (mFormat == Jpeg_Config::FORMAT_ABGR) {
    226         // Reverse endianness and set alphas to 255
    227         uint8_t* end = buf + len - 1;
    228         int r, g, b;
    229         for (int i = len - 1; i >= 0; i -= 4) {
    230             b = *--iter;
    231             g = *--iter;
    232             r = *--iter;
    233             buf[i] = r;
    234             buf[i - 1] = g;
    235             buf[i - 2] = b;
    236             buf[i - 3] = 255;
    237         }
    238     }
    239 }
    240 
    241 int32_t JpegReader::reset() {
    242     // Set jump address for error handling
    243     if (setjmp(mErrorManager.setjmp_buf)) {
    244         return J_ERROR_FATAL;
    245     }
    246     // Clean up global java references
    247     CleanSrc(&mInfo);
    248     // Wipe decompress struct, free memory pools
    249     jpeg_destroy_decompress(&mInfo);
    250     mFinished = false;
    251     mSetup = false;
    252     return J_SUCCESS;
    253 }
    254 
    255