// Copyright 2011 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// Simple OpenGL-based WebP file viewer.
//
// Author: Skal (pascal.massimino@gmail.com)
#ifdef HAVE_CONFIG_H
#include "webp/config.h"
#endif
#if defined(__unix__) || defined(__CYGWIN__)
#define _POSIX_C_SOURCE 200112L // for setenv
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if defined(WEBP_HAVE_GL)
#if defined(HAVE_GLUT_GLUT_H)
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#ifdef FREEGLUT
#include <GL/freeglut.h>
#endif
#endif
#ifdef WEBP_HAVE_QCMS
#include <qcms.h>
#endif
#include "webp/decode.h"
#include "webp/demux.h"
#include "../examples/example_util.h"
#include "../imageio/imageio_util.h"
#include "./unicode.h"
#if defined(_MSC_VER) && _MSC_VER < 1900
#define snprintf _snprintf
#endif
// Unfortunate global variables. Gathered into a struct for comfort.
static struct {
int has_animation;
int has_color_profile;
int done;
int decoding_error;
int print_info;
int only_deltas;
int use_color_profile;
int draw_anim_background_color;
int canvas_width, canvas_height;
int loop_count;
uint32_t bg_color;
const char* file_name;
WebPData data;
WebPDecoderConfig config;
const WebPDecBuffer* pic;
WebPDemuxer* dmux;
WebPIterator curr_frame;
WebPIterator prev_frame;
WebPChunkIterator iccp;
int viewport_width, viewport_height;
} kParams;
static void ClearPreviousPic(void) {
WebPFreeDecBuffer((WebPDecBuffer*)kParams.pic);
kParams.pic = NULL;
}
static void ClearParams(void) {
ClearPreviousPic();
WebPDataClear(&kParams.data);
WebPDemuxReleaseIterator(&kParams.curr_frame);
WebPDemuxReleaseIterator(&kParams.prev_frame);
WebPDemuxReleaseChunkIterator(&kParams.iccp);
WebPDemuxDelete(kParams.dmux);
kParams.dmux = NULL;
}
// Sets the previous frame to the dimensions of the canvas and has it dispose
// to background to cause the canvas to be cleared.
static void ClearPreviousFrame(void) {
WebPIterator* const prev = &kParams.prev_frame;
prev->width = kParams.canvas_width;
prev->height = kParams.canvas_height;
prev->x_offset = prev->y_offset = 0;
prev->dispose_method = WEBP_MUX_DISPOSE_BACKGROUND;
}
// -----------------------------------------------------------------------------
// Color profile handling
static int ApplyColorProfile(const WebPData* const profile,
WebPDecBuffer* const rgba) {
#ifdef WEBP_HAVE_QCMS
int i, ok = 0;
uint8_t* line;
uint8_t major_revision;
qcms_profile* input_profile = NULL;
qcms_profile* output_profile = NULL;
qcms_transform* transform = NULL;
const qcms_data_type input_type = QCMS_DATA_RGBA_8;
const qcms_data_type output_type = QCMS_DATA_RGBA_8;
const qcms_intent intent = QCMS_INTENT_DEFAULT;
if (profile == NULL || rgba == NULL) return 0;
if (profile->bytes == NULL || profile->size < 10) return 1;
major_revision = profile->bytes[8];
qcms_enable_iccv4();
input_profile = qcms_profile_from_memory(profile->bytes, profile->size);
// qcms_profile_is_bogus() is broken with ICCv4.
if (input_profile == NULL ||
(major_revision < 4 && qcms_profile_is_bogus(input_profile))) {
fprintf(stderr, "Color profile is bogus!\n");
goto Error;
}
output_profile = qcms_profile_sRGB();
if (output_profile == NULL) {
fprintf(stderr, "Error creating output color profile!\n");
goto Error;
}
qcms_profile_precache_output_transform(output_profile);
transform = qcms_transform_create(input_profile, input_type,
output_profile, output_type,
intent);
if (transform == NULL) {
fprintf(stderr, "Error creating color transform!\n");
goto Error;
}
line = rgba->u.RGBA.rgba;
for (i = 0; i < rgba->height; ++i, line += rgba->u.RGBA.stride) {
qcms_transform_data(transform, line, line, rgba->width);
}
ok = 1;
Error:
if (input_profile != NULL) qcms_profile_release(input_profile);
if (output_profile != NULL) qcms_profile_release(output_profile);
if (transform != NULL) qcms_transform_release(transform);
return ok;
#else
(void)profile;
(void)rgba;
return 1;
#endif // WEBP_HAVE_QCMS
}
//------------------------------------------------------------------------------
// File decoding
static int Decode(void) { // Fills kParams.curr_frame
const WebPIterator* const curr = &kParams.curr_frame;
WebPDecoderConfig* const config = &kParams.config;
WebPDecBuffer* const output_buffer = &config->output;
int ok = 0;
ClearPreviousPic();
output_buffer->colorspace = MODE_RGBA;
ok = (WebPDecode(curr->fragment.bytes, curr->fragment.size,
config) == VP8_STATUS_OK);
if (!ok) {
fprintf(stderr, "Decoding of frame #%d failed!\n", curr->frame_num);
} else {
kParams.pic = output_buffer;
if (kParams.use_color_profile) {
ok = ApplyColorProfile(&kParams.iccp.chunk, output_buffer);
if (!ok) {
fprintf(stderr, "Applying color profile to frame #%d failed!\n",
curr->frame_num);
}
}
}
return ok;
}
static void decode_callback(int what) {
if (what == 0 && !kParams.done) {
int duration = 0;
if (kParams.dmux != NULL) {
WebPIterator* const curr = &kParams.curr_frame;
if (!WebPDemuxNextFrame(curr)) {
WebPDemuxReleaseIterator(curr);
if (WebPDemuxGetFrame(kParams.dmux, 1, curr)) {
--kParams.loop_count;
kParams.done = (kParams.loop_count == 0);
if (kParams.done) return;
ClearPreviousFrame();
} else {
kParams.decoding_error = 1;
kParams.done = 1;
return;
}
}
duration = curr->duration;
// Behavior copied from Chrome, cf:
// https://cs.chromium.org/chromium/src/third_party/WebKit/Source/
// platform/graphics/DeferredImageDecoder.cpp?
// rcl=b4c33049f096cd283f32be9a58b9a9e768227c26&l=246
if (duration <= 10) duration = 100;
}
if (!Decode()) {
kParams.decoding_error = 1;
kParams.done = 1;
} else {
glutPostRedisplay();
glutTimerFunc(duration, decode_callback, what);
}
}
}
//------------------------------------------------------------------------------
// Callbacks
static void HandleKey(unsigned char key, int pos_x, int pos_y) {
// Note: rescaling the window or toggling some features during an animation
// generates visual artifacts. This is not fixed because refreshing the frame
// may require rendering the whole animation from start till current frame.
(void)pos_x;
(void)pos_y;
if (key == 'q' || key == 'Q' || key == 27 /* Esc */) {
#ifdef FREEGLUT
glutLeaveMainLoop();
#else
ClearParams();
exit(0);
#endif
} else if (key == 'c') {
if (kParams.has_color_profile && !kParams.decoding_error) {
kParams.use_color_profile = 1 - kParams.use_color_profile;
if (kParams.has_animation) {
// Restart the completed animation to pickup the color profile change.
if (kParams.done && kParams.loop_count == 0) {
kParams.loop_count =
(int)WebPDemuxGetI(kParams.dmux, WEBP_FF_LOOP_COUNT) + 1;
kParams.done = 0;
// Start the decode loop immediately.
glutTimerFunc(0, decode_callback, 0);
}
} else {
Decode();
glutPostRedisplay();
}
}
} else if (key == 'b') {
kParams.draw_anim_background_color = 1 - kParams.draw_anim_background_color;
if (!kParams.has_animation) ClearPreviousFrame();
glutPostRedisplay();
} else if (key == 'i') {
kParams.print_info = 1 - kParams.print_info;
if (!kParams.has_animation) ClearPreviousFrame();
glutPostRedisplay();
} else if (key == 'd') {
kParams.only_deltas = 1 - kParams.only_deltas;
glutPostRedisplay();
}
}
static void HandleReshape(int width, int height) {
// Note: reshape doesn't preserve aspect ratio, and might
// be handling larger-than-screen pictures incorrectly.
glViewport(0, 0, width, height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
kParams.viewport_width = width;
kParams.viewport_height = height;
if (!kParams.has_animation) ClearPreviousFrame();
}
static void PrintString(const char* const text) {
void* const font = GLUT_BITMAP_9_BY_15;
int i;
for (i = 0; text[i]; ++i) {
glutBitmapCharacter(font, text[i]);
}
}
static float GetColorf(uint32_t color, int shift) {
return ((color >> shift) & 0xff) / 255.f;
}
static void DrawCheckerBoard(void) {
const int square_size = 8; // must be a power of 2
int x, y;
GLint viewport[4]; // x, y, width, height
glPushMatrix();
glGetIntegerv(GL_VIEWPORT, viewport);
// shift to integer coordinates with (0,0) being top-left.
glOrtho(0, viewport[2], viewport[3], 0, -1, 1);
for (y = 0; y < viewport[3]; y += square_size) {
for (x = 0; x < viewport[2]; x += square_size) {
const GLubyte color = 128 + 64 * (!((x + y) & square_size));
glColor3ub(color, color, color);
glRecti(x, y, x + square_size, y + square_size);
}
}
glPopMatrix();
}
static void DrawBackground(void) {
// Whole window cleared with clear color, checkerboard rendered on top of it.
glClear(GL_COLOR_BUFFER_BIT);
DrawCheckerBoard();
// ANIM background color rendered (blend) on top. Default is white for still
// images (without ANIM chunk). glClear() can't be used for that (no blend).
if (kParams.draw_anim_background_color) {
glPushMatrix();
glLoadIdentity();
glColor4f(GetColorf(kParams.bg_color, 16), // BGRA from spec
GetColorf(kParams.bg_color, 8),
GetColorf(kParams.bg_color, 0),
GetColorf(kParams.bg_color, 24));
glRecti(-1, -1, +1, +1);
glPopMatrix();
}
}
// Draw background in a scissored rectangle.
static void DrawBackgroundScissored(int window_x, int window_y, int frame_w,
int frame_h) {
// Only update the requested area, not the whole canvas.
window_x = window_x * kParams.viewport_width / kParams.canvas_width;
window_y = window_y * kParams.viewport_height / kParams.canvas_height;
frame_w = frame_w * kParams.viewport_width / kParams.canvas_width;
frame_h = frame_h * kParams.viewport_height / kParams.canvas_height;
// glScissor() takes window coordinates (0,0 at bottom left).
window_y = kParams.viewport_height - window_y - frame_h;
glEnable(GL_SCISSOR_TEST);
glScissor(window_x, window_y, frame_w, frame_h);
DrawBackground();
glDisable(GL_SCISSOR_TEST);
}
static void HandleDisplay(void) {
const WebPDecBuffer* const pic = kParams.pic;
const WebPIterator* const curr = &kParams.curr_frame;
WebPIterator* const prev = &kParams.prev_frame;
GLfloat xoff, yoff;
if (pic == NULL) return;
glPushMatrix();
glPixelZoom((GLfloat)(+1. / kParams.canvas_width * kParams.viewport_width),
(GLfloat)(-1. / kParams.canvas_height * kParams.viewport_height));
xoff = (GLfloat)(2. * curr->x_offset / kParams.canvas_width);
yoff = (GLfloat)(2. * curr->y_offset / kParams.canvas_height);
glRasterPos2f(-1.f + xoff, 1.f - yoff);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glPixelStorei(GL_UNPACK_ROW_LENGTH, pic->u.RGBA.stride / 4);
if (kParams.only_deltas) {
DrawBackground();
} else {
// The rectangle of the previous frame might be different than the current
// frame, so we may need to DrawBackgroundScissored for both.
if (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) {
// Clear the previous frame rectangle.
DrawBackgroundScissored(prev->x_offset, prev->y_offset, prev->width,
prev->height);
}
if (curr->blend_method == WEBP_MUX_NO_BLEND) {
// We simulate no-blending behavior by first clearing the current frame
// rectangle and then alpha-blending against it.
DrawBackgroundScissored(curr->x_offset, curr->y_offset, curr->width,
curr->height);
}
}
*prev = *curr;
glDrawPixels(pic->width, pic->height,
GL_RGBA, GL_UNSIGNED_BYTE,
(GLvoid*)pic->u.RGBA.rgba);
if (kParams.print_info) {
char tmp[32];
glColor4f(0.90f, 0.0f, 0.90f, 1.0f);
glRasterPos2f(-0.95f, 0.90f);
PrintString(kParams.file_name);
snprintf(tmp, sizeof(tmp), "Dimension:%d x %d", pic->width, pic->height);
glColor4f(0.90f, 0.0f, 0.90f, 1.0f);
glRasterPos2f(-0.95f, 0.80f);
PrintString(tmp);
if (curr->x_offset != 0 || curr->y_offset != 0) {
snprintf(tmp, sizeof(tmp), " (offset:%d,%d)",
curr->x_offset, curr->y_offset);
glRasterPos2f(-0.95f, 0.70f);
PrintString(tmp);
}
}
glPopMatrix();
#if defined(__APPLE__) || defined(_WIN32)
glFlush();
#else
glutSwapBuffers();
#endif
}
static void StartDisplay(void) {
int width = kParams.canvas_width;
int height = kParams.canvas_height;
int screen_width, screen_height;
// TODO(webp:365) GLUT_DOUBLE results in flickering / old frames to be
// partially displayed with animated webp + alpha.
#if defined(__APPLE__) || defined(_WIN32)
glutInitDisplayMode(GLUT_RGBA);
#else
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);
#endif
screen_width = glutGet(GLUT_SCREEN_WIDTH);
screen_height = glutGet(GLUT_SCREEN_HEIGHT);
if (width > screen_width || height > screen_height) {
if (width > screen_width) {
height = (height * screen_width + width - 1) / width;
width = screen_width;
}
if (height > screen_height) {
width = (width * screen_height + height - 1) / height;
height = screen_height;
}
}
glutInitWindowSize(width, height);
glutCreateWindow("WebP viewer");
glutDisplayFunc(HandleDisplay);
glutReshapeFunc(HandleReshape);
glutIdleFunc(NULL);
glutKeyboardFunc(HandleKey);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glClearColor(0, 0, 0, 0); // window will be cleared to black (no blend)
DrawBackground();
}
//------------------------------------------------------------------------------
// Main
static void Help(void) {
printf(
"Usage: vwebp in_file [options]\n\n"
"Decodes the WebP image file and visualize it using OpenGL\n"
"Options are:\n"
" -version ..... print version number and exit\n"
" -noicc ....... don't use the icc profile if present\n"
" -nofancy ..... don't use the fancy YUV420 upscaler\n"
" -nofilter .... disable in-loop filtering\n"
" -dither <int> dithering strength (0..100), default=50\n"
" -noalphadither disable alpha plane dithering\n"
" -usebgcolor .. display background color\n"
" -mt .......... use multi-threading\n"
" -info ........ print info\n"
" -h ........... this help message\n"
"\n"
"Keyboard shortcuts:\n"
" 'c' ................ toggle use of color profile\n"
" 'b' ................ toggle background color display\n"
" 'i' ................ overlay file information\n"
" 'd' ................ disable blending & disposal (debug)\n"
" 'q' / 'Q' / ESC .... quit\n");
}
int main(int argc, char* argv[]) {
int c;
WebPDecoderConfig* const config = &kParams.config;
WebPIterator* const curr = &kParams.curr_frame;
INIT_WARGV(argc, argv);
if (!WebPInitDecoderConfig(config)) {
fprintf(stderr, "Library version mismatch!\n");
FREE_WARGV_AND_RETURN(-1);
}
config->options.dithering_strength = 50;
config->options.alpha_dithering_strength = 100;
kParams.use_color_profile = 1;
// Background color hidden by default to see transparent areas.
kParams.draw_anim_background_color = 0;
for (c = 1; c < argc; ++c) {
int parse_error = 0;
if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
Help();
FREE_WARGV_AND_RETURN(0);
} else if (!strcmp(argv[c], "-noicc")) {
kParams.use_color_profile = 0;
} else if (!strcmp(argv[c], "-nofancy")) {
config->options.no_fancy_upsampling = 1;
} else if (!strcmp(argv[c], "-nofilter")) {
config->options.bypass_filtering = 1;
} else if (!strcmp(argv[c], "-noalphadither")) {
config->options.alpha_dithering_strength = 0;
} else if (!strcmp(argv[c], "-usebgcolor")) {
kParams.draw_anim_background_color = 1;
} else if (!strcmp(argv[c], "-dither") && c + 1 < argc) {
config->options.dithering_strength =
ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-info")) {
kParams.print_info = 1;
} else if (!strcmp(argv[c], "-version")) {
const int dec_version = WebPGetDecoderVersion();
const int dmux_version = WebPGetDemuxVersion();
printf("WebP Decoder version: %d.%d.%d\nWebP Demux version: %d.%d.%d\n",
(dec_version >> 16) & 0xff, (dec_version >> 8) & 0xff,
dec_version & 0xff, (dmux_version >> 16) & 0xff,
(dmux_version >> 8) & 0xff, dmux_version & 0xff);
FREE_WARGV_AND_RETURN(0);
} else if (!strcmp(argv[c], "-mt")) {
config->options.use_threads = 1;
} else if (!strcmp(argv[c], "--")) {
if (c < argc - 1) kParams.file_name = (const char*)GET_WARGV(argv, ++c);
break;
} else if (argv[c][0] == '-') {
printf("Unknown option '%s'\n", argv[c]);
Help();
FREE_WARGV_AND_RETURN(-1);
} else {
kParams.file_name = (const char*)GET_WARGV(argv, c);
}
if (parse_error) {
Help();
FREE_WARGV_AND_RETURN(-1);
}
}
if (kParams.file_name == NULL) {
printf("missing input file!!\n");
Help();
FREE_WARGV_AND_RETURN(0);
}
if (!ImgIoUtilReadFile(kParams.file_name,
&kParams.data.bytes, &kParams.data.size)) {
goto Error;
}
if (!WebPGetInfo(kParams.data.bytes, kParams.data.size, NULL, NULL)) {
fprintf(stderr, "Input file doesn't appear to be WebP format.\n");
goto Error;
}
kParams.dmux = WebPDemux(&kParams.data);
if (kParams.dmux == NULL) {
fprintf(stderr, "Could not create demuxing object!\n");
goto Error;
}
kParams.canvas_width = WebPDemuxGetI(kParams.dmux, WEBP_FF_CANVAS_WIDTH);
kParams.canvas_height = WebPDemuxGetI(kParams.dmux, WEBP_FF_CANVAS_HEIGHT);
if (kParams.print_info) {
printf("Canvas: %d x %d\n", kParams.canvas_width, kParams.canvas_height);
}
ClearPreviousFrame();
memset(&kParams.iccp, 0, sizeof(kParams.iccp));
kParams.has_color_profile =
!!(WebPDemuxGetI(kParams.dmux, WEBP_FF_FORMAT_FLAGS) & ICCP_FLAG);
if (kParams.has_color_profile) {
#ifdef WEBP_HAVE_QCMS
if (!WebPDemuxGetChunk(kParams.dmux, "ICCP", 1, &kParams.iccp)) goto Error;
printf("VP8X: Found color profile\n");
#else
fprintf(stderr, "Warning: color profile present, but qcms is unavailable!\n"
"Build libqcms from Mozilla or Chromium and define WEBP_HAVE_QCMS "
"before building.\n");
#endif
}
if (!WebPDemuxGetFrame(kParams.dmux, 1, curr)) goto Error;
kParams.has_animation = (curr->num_frames > 1);
kParams.loop_count = (int)WebPDemuxGetI(kParams.dmux, WEBP_FF_LOOP_COUNT);
kParams.bg_color = WebPDemuxGetI(kParams.dmux, WEBP_FF_BACKGROUND_COLOR);
printf("VP8X: Found %d images in file (loop count = %d)\n",
curr->num_frames, kParams.loop_count);
// Decode first frame
if (!Decode()) goto Error;
// Position iterator to last frame. Next call to HandleDisplay will wrap over.
// We take this into account by bumping up loop_count.
WebPDemuxGetFrame(kParams.dmux, 0, curr);
if (kParams.loop_count) ++kParams.loop_count;
#if defined(__unix__) || defined(__CYGWIN__)
// Work around GLUT compositor bug.
// https://bugs.launchpad.net/ubuntu/+source/freeglut/+bug/369891
setenv("XLIB_SKIP_ARGB_VISUALS", "1", 1);
#endif
// Start display (and timer)
glutInit(&argc, argv);
#ifdef FREEGLUT
glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_CONTINUE_EXECUTION);
#endif
StartDisplay();
if (kParams.has_animation) glutTimerFunc(0, decode_callback, 0);
glutMainLoop();
// Should only be reached when using FREEGLUT:
ClearParams();
FREE_WARGV_AND_RETURN(0);
Error:
ClearParams();
FREE_WARGV_AND_RETURN(-1);
}
#else // !WEBP_HAVE_GL
int main(int argc, const char* argv[]) {
fprintf(stderr, "OpenGL support not enabled in %s.\n", argv[0]);
(void)argc;
return 0;
}
#endif
//------------------------------------------------------------------------------