jpeg.c

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/*
 * Copyright 2004 James Bursa <bursa@users.sourceforge.net>
 * Copyright 2004 John M Bell <jmb202@ecs.soton.ac.uk>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf 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; version 2 of the License.
 *
 * NetSurf 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/>.
 */
 
/**
 * \file
 * implementation of content handling for image/jpeg
 *
 * This implementation uses the IJG JPEG library.
 */
 
#include <stdbool.h>
#include <stdlib.h>
#include <setjmp.h>
 
#include "utils/utils.h"
#include "utils/log.h"
#include "utils/messages.h"
#include "netsurf/bitmap.h"
#include "content/llcache.h"
#include "content/content.h"
#include "content/content_protected.h"
#include "content/content_factory.h"
#include "desktop/gui_internal.h"
#include "desktop/bitmap.h"
 
#include "image/image_cache.h"
 
#define JPEG_INTERNAL_OPTIONS
#include "jpeglib.h"
#include "jpeg.h"
 
/** absolute minimum size of a jpeg below which it is not even worth
 * trying to read header data
 */
#define MIN_JPEG_SIZE 20
 
#ifndef LIBJPEG_TURBO_VERSION
#warning Using libjpeg (libjpeg-turbo is recommended)
#endif
 
static char nsjpeg_error_buffer[JMSG_LENGTH_MAX];
 
static unsigned char nsjpeg_eoi[] = { 0xff, JPEG_EOI };
 
/**
 * Content create entry point.
 */
static nserror nsjpeg_create(const content_handler *handler,
                lwc_string *imime_type, const struct http_parameter *params,
                llcache_handle *llcache, const char *fallback_charset,
                bool quirks, struct content **c)
{
        struct content *jpeg;
        nserror error;
 
        jpeg = calloc(1, sizeof(struct content));
        if (jpeg == NULL)
                return NSERROR_NOMEM;
 
        error = content__init(jpeg, handler, imime_type, params,
                              llcache, fallback_charset, quirks);
        if (error != NSERROR_OK) {
                free(jpeg);
                return error;
        }
 
        *c = jpeg;
 
        return NSERROR_OK;
}
 
/**
 * JPEG data source manager: initialize source.
 */
static void nsjpeg_init_source(j_decompress_ptr cinfo)
{
}
 
 
/**
 * JPEG data source manager: fill the input buffer.
 *
 * This can only occur if the JPEG data was truncated or corrupted. Insert a
 * fake EOI marker to allow the decompressor to output as much as possible.
 */
static boolean nsjpeg_fill_input_buffer(j_decompress_ptr cinfo)
{
        cinfo->src->next_input_byte = nsjpeg_eoi;
        cinfo->src->bytes_in_buffer = 2;
        return TRUE;
}
 
 
/**
 * JPEG data source manager: skip num_bytes worth of data.
 */
 
static void nsjpeg_skip_input_data(j_decompress_ptr cinfo, long num_bytes)
{
        if ((long) cinfo->src->bytes_in_buffer < num_bytes) {
                cinfo->src->next_input_byte = 0;
                cinfo->src->bytes_in_buffer = 0;
        } else {
                cinfo->src->next_input_byte += num_bytes;
                cinfo->src->bytes_in_buffer -= num_bytes;
        }
}
 
 
/**
 * JPEG data source manager: terminate source.
 */
static void nsjpeg_term_source(j_decompress_ptr cinfo)
{
}
 
 
/**
 * Error output handler for JPEG library.
 *
 * This logs to NetSurf log instead of stderr.
 * Warnings only - fatal errors are trapped by nsjpeg_error_exit
 *                 and do not call the output handler.
 */
static void nsjpeg_error_log(j_common_ptr cinfo)
{
        cinfo->err->format_message(cinfo, nsjpeg_error_buffer);
        NSLOG(netsurf, INFO, "%s", nsjpeg_error_buffer);
}
 
 
/**
 * Fatal error handler for JPEG library.
 *
 * This prevents jpeglib calling exit() on a fatal error.
 */
static void nsjpeg_error_exit(j_common_ptr cinfo)
{
        jmp_buf *setjmp_buffer = (jmp_buf *) cinfo->client_data;
 
        cinfo->err->format_message(cinfo, nsjpeg_error_buffer);
        NSLOG(netsurf, INFO, "%s", nsjpeg_error_buffer);
 
        longjmp(*setjmp_buffer, 1);
}
 
/**
 * Convert scan lines from CMYK to core client bitmap layout.
 */
static inline void nsjpeg__decode_cmyk(
                struct jpeg_decompress_struct *cinfo,
                uint8_t * volatile pixels,
                size_t rowstride)
{
        int width = cinfo->output_width * 4;
 
        do {
                JSAMPROW scanlines[1] = {
                        [0] = (JSAMPROW)
                                (pixels + rowstride * cinfo->output_scanline),
                };
                jpeg_read_scanlines(cinfo, scanlines, 1);
 
                for (int i = width - 4; 0 <= i; i -= 4) {
                        /* Trivial inverse CMYK -> RGBA */
                        const int c = scanlines[0][i + 0];
                        const int m = scanlines[0][i + 1];
                        const int y = scanlines[0][i + 2];
                        const int k = scanlines[0][i + 3];
 
                        const int ck = c * k;
                        const int mk = m * k;
                        const int yk = y * k;
 
#define DIV255(x) ((x) + 1 + ((x) >> 8)) >> 8
                        scanlines[0][i + bitmap_layout.r] = DIV255(ck);
                        scanlines[0][i + bitmap_layout.g] = DIV255(mk);
                        scanlines[0][i + bitmap_layout.b] = DIV255(yk);
                        scanlines[0][i + bitmap_layout.a] = 0xff;
#undef DIV255
                }
        } while (cinfo->output_scanline != cinfo->output_height);
}
 
/**
 * Convert scan lines from CMYK to core client bitmap layout.
 */
static inline void nsjpeg__decode_rgb(
                struct jpeg_decompress_struct *cinfo,
                uint8_t * volatile pixels,
                size_t rowstride)
{
#if RGB_RED != 0 || RGB_GREEN != 1 || RGB_BLUE != 2 || RGB_PIXELSIZE != 4
        int width = cinfo->output_width;
#endif
 
        do {
                JSAMPROW scanlines[1] = {
                        [0] = (JSAMPROW)
                                (pixels + rowstride * cinfo->output_scanline),
                };
                jpeg_read_scanlines(cinfo, scanlines, 1);
 
#if RGB_RED != 0 || RGB_GREEN != 1 || RGB_BLUE != 2 || RGB_PIXELSIZE != 4
                /* Missmatch between configured libjpeg pixel format and
                 * NetSurf pixel format.  Convert to RGBA */
                for (int i = width - 1; 0 <= i; i--) {
                        int r = scanlines[0][i * RGB_PIXELSIZE + RGB_RED];
                        int g = scanlines[0][i * RGB_PIXELSIZE + RGB_GREEN];
                        int b = scanlines[0][i * RGB_PIXELSIZE + RGB_BLUE];
                        scanlines[0][i * 4 + bitmap_layout.r] = r;
                        scanlines[0][i * 4 + bitmap_layout.g] = g;
                        scanlines[0][i * 4 + bitmap_layout.b] = b;
                        scanlines[0][i * 4 + bitmap_layout.a] = 0xff;
                }
#endif
        } while (cinfo->output_scanline != cinfo->output_height);
}
 
/**
 * Convert scan lines from CMYK to core client bitmap layout.
 */
static inline void nsjpeg__decode_client_fmt(
                struct jpeg_decompress_struct *cinfo,
                uint8_t * volatile pixels,
                size_t rowstride)
{
        do {
                JSAMPROW scanlines[1] = {
                        [0] = (JSAMPROW)
                                (pixels + rowstride * cinfo->output_scanline),
                };
                jpeg_read_scanlines(cinfo, scanlines, 1);
        } while (cinfo->output_scanline != cinfo->output_height);
}
 
/**
 * create a bitmap from jpeg content.
 */
static struct bitmap *
jpeg_cache_convert(struct content *c)
{
        const uint8_t *source_data; /* Jpeg source data */
        size_t source_size; /* length of Jpeg source data */
        struct jpeg_decompress_struct cinfo;
        struct jpeg_error_mgr jerr;
        jmp_buf setjmp_buffer;
        struct bitmap * volatile bitmap = NULL;
        uint8_t * volatile pixels = NULL;
        size_t rowstride;
        struct jpeg_source_mgr source_mgr = {
                0,
                0,
                nsjpeg_init_source,
                nsjpeg_fill_input_buffer,
                nsjpeg_skip_input_data,
                jpeg_resync_to_restart,
                nsjpeg_term_source };
 
        /* obtain jpeg source data and perfom minimal sanity checks */
        source_data = content__get_source_data(c, &source_size);
 
        if ((source_data == NULL) ||
            (source_size < MIN_JPEG_SIZE)) {
                return NULL;
        }
 
        /* setup a JPEG library error handler */
        cinfo.err = jpeg_std_error(&jerr);
        jerr.error_exit = nsjpeg_error_exit;
        jerr.output_message = nsjpeg_error_log;
 
        /* handler for fatal errors during decompression */
        if (setjmp(setjmp_buffer)) {
                jpeg_destroy_decompress(&cinfo);
                return bitmap;
        }
 
        cinfo.client_data = &setjmp_buffer;
        jpeg_create_decompress(&cinfo);
 
        /* setup data source */
        source_mgr.next_input_byte = source_data;
        source_mgr.bytes_in_buffer = source_size;
        cinfo.src = &source_mgr;
 
        /* read JPEG header information */
        jpeg_read_header(&cinfo, TRUE);
 
        /* set output processing parameters */
        if (cinfo.jpeg_color_space == JCS_CMYK ||
            cinfo.jpeg_color_space == JCS_YCCK) {
                cinfo.out_color_space = JCS_CMYK;
        } else {
#ifdef JCS_ALPHA_EXTENSIONS
                switch (bitmap_fmt.layout) {
                case BITMAP_LAYOUT_R8G8B8A8:
                        cinfo.out_color_space = JCS_EXT_RGBA;
                        break;
                case BITMAP_LAYOUT_B8G8R8A8:
                        cinfo.out_color_space = JCS_EXT_BGRA;
                        break;
                case BITMAP_LAYOUT_A8R8G8B8:
                        cinfo.out_color_space = JCS_EXT_ARGB;
                        break;
                case BITMAP_LAYOUT_A8B8G8R8:
                        cinfo.out_color_space = JCS_EXT_ABGR;
                        break;
                default:
                        NSLOG(netsurf, ERROR, "Unexpected bitmap format: %u",
                                        bitmap_fmt.layout);
                        jpeg_destroy_decompress(&cinfo);
                        return NULL;
                }
#else
                cinfo.out_color_space = JCS_RGB;
#endif
        }
        cinfo.dct_method = JDCT_ISLOW;
 
        /* commence the decompression, output parameters now valid */
        jpeg_start_decompress(&cinfo);
 
        /* create opaque bitmap (jpegs cannot be transparent) */
        bitmap = guit->bitmap->create(
                        cinfo.output_width,
                        cinfo.output_height, BITMAP_OPAQUE);
        if (bitmap == NULL) {
                /* empty bitmap could not be created */
                jpeg_destroy_decompress(&cinfo);
                return NULL;
        }
 
        pixels = guit->bitmap->get_buffer(bitmap);
        if (pixels == NULL) {
                /* bitmap with no buffer available */
                guit->bitmap->destroy(bitmap);
                jpeg_destroy_decompress(&cinfo);
                return NULL;
        }
 
        /* Convert scanlines from jpeg into bitmap */
        rowstride = guit->bitmap->get_rowstride(bitmap);
 
        switch (cinfo.out_color_space) {
        case JCS_CMYK:
                nsjpeg__decode_cmyk(&cinfo, pixels, rowstride);
                break;
 
        case JCS_RGB:
                nsjpeg__decode_rgb(&cinfo, pixels, rowstride);
                break;
 
        default:
                nsjpeg__decode_client_fmt(&cinfo, pixels, rowstride);
                break;
        }
 
        guit->bitmap->modified(bitmap);
 
        jpeg_finish_decompress(&cinfo);
        jpeg_destroy_decompress(&cinfo);
 
        return bitmap;
}
 
/**
 * Convert a CONTENT_JPEG for display.
 */
static bool nsjpeg_convert(struct content *c)
{
        struct jpeg_decompress_struct cinfo;
        struct jpeg_error_mgr jerr;
        jmp_buf setjmp_buffer;
        struct jpeg_source_mgr source_mgr = { 0, 0,
                nsjpeg_init_source, nsjpeg_fill_input_buffer,
                nsjpeg_skip_input_data, jpeg_resync_to_restart,
                nsjpeg_term_source };
        union content_msg_data msg_data;
        const uint8_t *data;
        size_t size;
        char *title;
 
        /* check image header is valid and get width/height */
        data = content__get_source_data(c, &size);
 
        cinfo.err = jpeg_std_error(&jerr);
        jerr.error_exit = nsjpeg_error_exit;
        jerr.output_message = nsjpeg_error_log;
 
        if (setjmp(setjmp_buffer)) {
                jpeg_destroy_decompress(&cinfo);
 
                msg_data.errordata.errorcode = NSERROR_UNKNOWN;
                msg_data.errordata.errormsg = nsjpeg_error_buffer;
                content_broadcast(c, CONTENT_MSG_ERROR, &msg_data);
                return false;
        }
 
        cinfo.client_data = &setjmp_buffer;
        jpeg_create_decompress(&cinfo);
        source_mgr.next_input_byte = (unsigned char *) data;
        source_mgr.bytes_in_buffer = size;
        cinfo.src = &source_mgr;
        jpeg_read_header(&cinfo, TRUE);
        cinfo.out_color_space = JCS_RGB;
        cinfo.dct_method = JDCT_ISLOW;
 
        jpeg_calc_output_dimensions(&cinfo);
 
        c->width = cinfo.output_width;
        c->height = cinfo.output_height;
        c->size = c->width * c->height * 4;
 
        jpeg_destroy_decompress(&cinfo);
 
        image_cache_add(c, NULL, jpeg_cache_convert);
 
        /* set title text */
        title = messages_get_buff("JPEGTitle",
                        nsurl_access_leaf(llcache_handle_get_url(c->llcache)),
                        c->width, c->height);
        if (title != NULL) {
                content__set_title(c, title);
                free(title);
        }
 
        content_set_ready(c);
        content_set_done(c);    
        content_set_status(c, ""); /* Done: update status bar */
 
        return true;
}
 
 
 
/**
 * Clone content.
 */
static nserror nsjpeg_clone(const struct content *old, struct content **newc)
{
        struct content *jpeg_c;
        nserror error;
 
        jpeg_c = calloc(1, sizeof(struct content));
        if (jpeg_c == NULL)
                return NSERROR_NOMEM;
 
        error = content__clone(old, jpeg_c);
        if (error != NSERROR_OK) {
                content_destroy(jpeg_c);
                return error;
        }
 
        /* re-convert if the content is ready */
        if ((old->status == CONTENT_STATUS_READY) ||
            (old->status == CONTENT_STATUS_DONE)) {
                if (nsjpeg_convert(jpeg_c) == false) {
                        content_destroy(jpeg_c);
                        return NSERROR_CLONE_FAILED;
                }
        }
 
        *newc = jpeg_c;
 
        return NSERROR_OK;
}
 
static const content_handler nsjpeg_content_handler = {
        .create = nsjpeg_create,
        .data_complete = nsjpeg_convert,
        .destroy = image_cache_destroy,
        .redraw = image_cache_redraw,
        .clone = nsjpeg_clone,
        .get_internal = image_cache_get_internal,
        .type = image_cache_content_type,
        .is_opaque = image_cache_is_opaque,
        .no_share = false,
};
 
static const char *nsjpeg_types[] = {
        "image/jpeg",
        "image/jpg",
        "image/pjpeg"
};
 
CONTENT_FACTORY_REGISTER_TYPES(nsjpeg, nsjpeg_types, nsjpeg_content_handler);