/src/gdk-pixbuf/gdk-pixbuf/io-gif-animation.c

Source
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -*- */
/* GdkPixbuf library - animated gif support
 *
 * Copyright (C) 1999 The Free Software Foundation
 *
 * Authors: Jonathan Blandford <jrb@redhat.com>
 *          Havoc Pennington <hp@redhat.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"
#include <string.h>
#include <errno.h>
#include "gdk-pixbuf-transform.h"
#include "io-gif-animation.h"
#include "lzw.h"

G_GNUC_BEGIN_IGNORE_DEPRECATIONS

static void gdk_pixbuf_gif_anim_finalize   (GObject        *object);

static gboolean                gdk_pixbuf_gif_anim_is_static_image  (GdkPixbufAnimation *animation);
static GdkPixbuf*              gdk_pixbuf_gif_anim_get_static_image (GdkPixbufAnimation *animation);

static void                    gdk_pixbuf_gif_anim_get_size (GdkPixbufAnimation *anim,
                                                             int                *width,
                                                             int                *height);
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
static GdkPixbufAnimationIter* gdk_pixbuf_gif_anim_get_iter (GdkPixbufAnimation *anim,
                                                             const GTimeVal     *start_time);
G_GNUC_END_IGNORE_DEPRECATIONS
static GdkPixbuf*              gdk_pixbuf_gif_anim_iter_get_pixbuf (GdkPixbufAnimationIter *iter);



G_DEFINE_TYPE (GdkPixbufGifAnim, gdk_pixbuf_gif_anim, GDK_TYPE_PIXBUF_ANIMATION);

static void
gdk_pixbuf_gif_anim_init (GdkPixbufGifAnim *anim)
{
}

static void
gdk_pixbuf_gif_anim_class_init (GdkPixbufGifAnimClass *klass)
{
        GObjectClass *object_class = G_OBJECT_CLASS (klass);
        GdkPixbufAnimationClass *anim_class = GDK_PIXBUF_ANIMATION_CLASS (klass);

        object_class->finalize = gdk_pixbuf_gif_anim_finalize;

        anim_class->is_static_image = gdk_pixbuf_gif_anim_is_static_image;
        anim_class->get_static_image = gdk_pixbuf_gif_anim_get_static_image;
        anim_class->get_size = gdk_pixbuf_gif_anim_get_size;
        anim_class->get_iter = gdk_pixbuf_gif_anim_get_iter;
}

static void
gdk_pixbuf_gif_anim_finalize (GObject *object)
{
        GdkPixbufGifAnim *gif_anim = GDK_PIXBUF_GIF_ANIM (object);

        GList *l;
        GdkPixbufFrame *frame;

        for (l = gif_anim->frames; l; l = l->next) {
                frame = l->data;
                g_byte_array_unref (frame->lzw_data);
                if (frame->color_map_allocated)
                        g_free (frame->color_map);
                g_free (frame);
        }

        g_list_free (gif_anim->frames);

        g_clear_object (&gif_anim->last_frame_data);
        g_clear_object (&gif_anim->last_frame_revert_data);

        G_OBJECT_CLASS (gdk_pixbuf_gif_anim_parent_class)->finalize (object);
}

static gboolean
gdk_pixbuf_gif_anim_is_static_image  (GdkPixbufAnimation *animation)
{
        GdkPixbufGifAnim *gif_anim;

        gif_anim = GDK_PIXBUF_GIF_ANIM (animation);

        return (gif_anim->frames != NULL &&
                gif_anim->frames->next == NULL);
}

G_GNUC_BEGIN_IGNORE_DEPRECATIONS
static GdkPixbuf*
gdk_pixbuf_gif_anim_get_static_image (GdkPixbufAnimation *animation)
{
        GdkPixbufGifAnim *gif_anim;
        GdkPixbufAnimationIter *iter;
        GdkPixbuf *pixbuf;
        GTimeVal start_time = { 0, 0 };

        gif_anim = GDK_PIXBUF_GIF_ANIM (animation);

        if (gif_anim->frames == NULL)
                return NULL;

        iter = gdk_pixbuf_gif_anim_get_iter (animation, &start_time);
        pixbuf = gdk_pixbuf_gif_anim_iter_get_pixbuf (iter);
        g_object_unref (iter);

        return pixbuf;
}
G_GNUC_END_IGNORE_DEPRECATIONS

static void
gdk_pixbuf_gif_anim_get_size (GdkPixbufAnimation *anim,
                              int                *width,
                              int                *height)
{
        GdkPixbufGifAnim *gif_anim;

        gif_anim = GDK_PIXBUF_GIF_ANIM (anim);

        if (width)
                *width = gif_anim->width;

        if (height)
                *height = gif_anim->height;
}


static void
iter_clear (GdkPixbufGifAnimIter *iter)
{
        iter->current_frame = NULL;
}

static void
iter_restart (GdkPixbufGifAnimIter *iter)
{
        iter_clear (iter);

        iter->current_frame = iter->gif_anim->frames;
}

G_GNUC_BEGIN_IGNORE_DEPRECATIONS
static GdkPixbufAnimationIter*
gdk_pixbuf_gif_anim_get_iter (GdkPixbufAnimation *anim,
                              const GTimeVal     *start_time)
{
        GdkPixbufGifAnimIter *iter;

        iter = g_object_new (GDK_TYPE_PIXBUF_GIF_ANIM_ITER, NULL);

        iter->gif_anim = GDK_PIXBUF_GIF_ANIM (anim);

        g_object_ref (iter->gif_anim);

        iter_restart (iter);

        iter->start_time = *start_time;
        iter->current_time = *start_time;
        iter->first_loop_slowness = 0;

        return GDK_PIXBUF_ANIMATION_ITER (iter);
}
G_GNUC_END_IGNORE_DEPRECATIONS



static void gdk_pixbuf_gif_anim_iter_finalize   (GObject                   *object);

static int        gdk_pixbuf_gif_anim_iter_get_delay_time             (GdkPixbufAnimationIter *iter);
static gboolean   gdk_pixbuf_gif_anim_iter_on_currently_loading_frame (GdkPixbufAnimationIter *iter);
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
static gboolean   gdk_pixbuf_gif_anim_iter_advance                    (GdkPixbufAnimationIter *iter,
                                                                       const GTimeVal         *current_time);
G_GNUC_END_IGNORE_DEPRECATIONS



G_DEFINE_TYPE (GdkPixbufGifAnimIter, gdk_pixbuf_gif_anim_iter, GDK_TYPE_PIXBUF_ANIMATION_ITER);

static void
gdk_pixbuf_gif_anim_iter_init (GdkPixbufGifAnimIter *iter)
{
}

static void
gdk_pixbuf_gif_anim_iter_class_init (GdkPixbufGifAnimIterClass *klass)
{
        GObjectClass *object_class = G_OBJECT_CLASS (klass);
        GdkPixbufAnimationIterClass *anim_iter_class =
                GDK_PIXBUF_ANIMATION_ITER_CLASS (klass);

        object_class->finalize = gdk_pixbuf_gif_anim_iter_finalize;

        anim_iter_class->get_delay_time = gdk_pixbuf_gif_anim_iter_get_delay_time;
        anim_iter_class->get_pixbuf = gdk_pixbuf_gif_anim_iter_get_pixbuf;
        anim_iter_class->on_currently_loading_frame = gdk_pixbuf_gif_anim_iter_on_currently_loading_frame;
        anim_iter_class->advance = gdk_pixbuf_gif_anim_iter_advance;
}

static void
gdk_pixbuf_gif_anim_iter_finalize (GObject *object)
{
        GdkPixbufGifAnimIter *iter = GDK_PIXBUF_GIF_ANIM_ITER (object);

        iter_clear (iter);

        g_object_unref (iter->gif_anim);

        G_OBJECT_CLASS (gdk_pixbuf_gif_anim_iter_parent_class)->finalize (object);
}

G_GNUC_BEGIN_IGNORE_DEPRECATIONS
static gboolean
gdk_pixbuf_gif_anim_iter_advance (GdkPixbufAnimationIter *anim_iter,
                                  const GTimeVal         *current_time)
{
        GdkPixbufGifAnimIter *iter;
        gint elapsed;
        gint loop;
        GList *tmp;
        GList *old;

        iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);

        iter->current_time = *current_time;

        /* We use milliseconds for all times */
        elapsed =
          (((iter->current_time.tv_sec - iter->start_time.tv_sec) * G_USEC_PER_SEC +
            iter->current_time.tv_usec - iter->start_time.tv_usec)) / 1000;

        if (elapsed < 0) {
                /* Try to compensate; probably the system clock
                 * was set backwards
                 */
                iter->start_time = iter->current_time;
                elapsed = 0;
        }

        g_assert (iter->gif_anim->total_time > 0);

        /* See how many times we've already played the full animation,
         * and subtract time for that.
         */

        /* If current_frame is NULL at this point, we have loaded the
         * animation from a source which fell behind the speed of the
         * display. We remember how much slower the first loop was due
         * to this and correct the position calculation in order to not
         * jump in the middle of the second loop.
         */
        if (iter->current_frame == NULL)
                iter->first_loop_slowness = MAX(0, elapsed - iter->gif_anim->total_time);

        loop = (elapsed - iter->first_loop_slowness) / iter->gif_anim->total_time;
        elapsed = (elapsed - iter->first_loop_slowness) % iter->gif_anim->total_time;

        iter->position = elapsed;

        /* Now move to the proper frame */
        if (iter->gif_anim->loop == 0 || loop < iter->gif_anim->loop)
                tmp = iter->gif_anim->frames;
        else
                tmp = NULL;
        while (tmp != NULL) {
                GdkPixbufFrame *frame = tmp->data;

                if (iter->position >= frame->elapsed &&
                    iter->position < (frame->elapsed + frame->delay_time))
                        break;

                tmp = tmp->next;
        }

        old = iter->current_frame;

        iter->current_frame = tmp;

        return iter->current_frame != old;
}
G_GNUC_END_IGNORE_DEPRECATIONS

int
gdk_pixbuf_gif_anim_iter_get_delay_time (GdkPixbufAnimationIter *anim_iter)
{
        GdkPixbufFrame *frame;
        GdkPixbufGifAnimIter *iter;

        iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);

        if (iter->current_frame) {
                frame = iter->current_frame->data;

#if 0
                g_print ("frame start: %d pos: %d frame len: %d frame remaining: %d\n",
                         frame->elapsed,
                         iter->position,
                         frame->delay_time,
                         frame->delay_time - (iter->position - frame->elapsed));
#endif

                return frame->delay_time - (iter->position - frame->elapsed);
        } else
                return -1; /* show last frame forever */
}

static void
composite_frame (GdkPixbufGifAnim *anim, GdkPixbufFrame *frame)
{
        LZWDecoder *lzw_decoder = NULL;
        guint8 *index_buffer = NULL;
        gsize n_indexes, i;
        guint16 *interlace_rows = NULL;
        guchar *pixels;

        anim->last_frame = frame;

        /* Store overwritten data if required */
        g_clear_object (&anim->last_frame_revert_data);
        if (frame->action == GDK_PIXBUF_FRAME_REVERT) {
                anim->last_frame_revert_data = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, frame->width, frame->height);
                if (anim->last_frame_revert_data != NULL)
                        gdk_pixbuf_copy_area (anim->last_frame_data,
                                              frame->x_offset, frame->y_offset, frame->width, frame->height,
                                              anim->last_frame_revert_data,
                                              0, 0);
        }

        lzw_decoder = lzw_decoder_new (frame->lzw_code_size + 1);
        index_buffer = g_new (guint8, frame->width * frame->height);
        if (index_buffer == NULL)
                goto out;

        interlace_rows = g_new (guint16, frame->height);
        if (interlace_rows == NULL)
                goto out;
        if (frame->interlace) {
                int row, n = 0;
                for (row = 0; row < frame->height; row += 8)
                        interlace_rows[n++] = row;
                for (row = 4; row < frame->height; row += 8)
                        interlace_rows[n++] = row;
                for (row = 2; row < frame->height; row += 4)
                        interlace_rows[n++] = row;
                for (row = 1; row < frame->height; row += 2)
                        interlace_rows[n++] = row;
        }
        else {
                int row;
                for (row = 0; row < frame->height; row++)
                        interlace_rows[row] = row;
        }

        n_indexes = lzw_decoder_feed (lzw_decoder, frame->lzw_data->data, frame->lzw_data->len, index_buffer, frame->width * frame->height);
        pixels = gdk_pixbuf_get_pixels (anim->last_frame_data);
        for (i = 0; i < n_indexes; i++) {
                guint8 index = index_buffer[i];
                guint x, y;
                gsize offset;

                if (index == frame->transparent_index)
                        continue;

                x = i % frame->width + frame->x_offset;
                y = interlace_rows[i / frame->width] + frame->y_offset;
                if (x >= anim->width || y >= anim->height)
                        continue;

                if (g_size_checked_mul (&offset, gdk_pixbuf_get_rowstride (anim->last_frame_data), y) &&
                    g_size_checked_add (&offset, offset, x * 4)) {
                        pixels[offset + 0] = frame->color_map[index * 3 + 0];
                        pixels[offset + 1] = frame->color_map[index * 3 + 1];
                        pixels[offset + 2] = frame->color_map[index * 3 + 2];
                        pixels[offset + 3] = 255;
                }
        }

out:
        g_clear_object (&lzw_decoder);
        g_free (index_buffer);
        g_free (interlace_rows);
}

GdkPixbuf*
gdk_pixbuf_gif_anim_iter_get_pixbuf (GdkPixbufAnimationIter *anim_iter)
{
        GdkPixbufGifAnimIter *iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);
        GdkPixbufGifAnim *anim = iter->gif_anim;
        GdkPixbufFrame *requested_frame;
        GList *link;

        if (iter->current_frame != NULL)
                requested_frame = iter->current_frame->data;
        else
                requested_frame = g_list_last (anim->frames)->data;

        /* If the previously rendered frame is not before this one, then throw it away */
        if (anim->last_frame != NULL) {
                link = g_list_find (anim->frames, anim->last_frame);
                while (link != NULL && link->data != requested_frame)
                        link = link->next;
                if (link == NULL)
                        anim->last_frame = NULL;
        }

        /* If no rendered frame, render the first frame */
        if (anim->last_frame == NULL) {
                gsize len = 0;
                if (anim->last_frame_data == NULL)
                        anim->last_frame_data = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, anim->width, anim->height);
                if (anim->last_frame_data == NULL)
                        return NULL;
                if (g_size_checked_mul (&len, gdk_pixbuf_get_rowstride (anim->last_frame_data), anim->height))
                        memset (gdk_pixbuf_get_pixels (anim->last_frame_data), 0, len);
                else
                        return NULL;
                composite_frame (anim, g_list_nth_data (anim->frames, 0));
        }

        /* If the requested frame is already rendered, then no action required */
        if (requested_frame == anim->last_frame)
                return anim->last_frame_data;

        /* Starting from the last rendered frame, render to the current frame */
        for (link = g_list_find (anim->frames, anim->last_frame); link->next != NULL && link->data != requested_frame; link = link->next) {
                GdkPixbufFrame *frame = link->data;
                guchar *pixels;
                int y, x_end, y_end;

                /* Remove last frame if required */
                switch (frame->action) {
                case GDK_PIXBUF_FRAME_RETAIN:
                        break;
                case GDK_PIXBUF_FRAME_DISPOSE:
                        /* Replace previous area with background */
                        pixels = gdk_pixbuf_get_pixels (anim->last_frame_data);
                        x_end = MIN (anim->last_frame->x_offset + anim->last_frame->width, anim->width);
                        y_end = MIN (anim->last_frame->y_offset + anim->last_frame->height, anim->height);
                        for (y = anim->last_frame->y_offset; y < y_end; y++) {
                                gsize offset;
                                if (g_size_checked_mul (&offset, gdk_pixbuf_get_rowstride (anim->last_frame_data), y) &&
                                    g_size_checked_add (&offset, offset, anim->last_frame->x_offset * 4)) {
                                         memset (pixels + offset, 0, (x_end - anim->last_frame->x_offset) * 4);
                                }
                        }
                        break;
                case GDK_PIXBUF_FRAME_REVERT:
                        /* Replace previous area with last retained area */
                        if (anim->last_frame_revert_data != NULL)
                                gdk_pixbuf_copy_area (anim->last_frame_revert_data,
                                                      0, 0, anim->last_frame->width, anim->last_frame->height,
                                                      anim->last_frame_data,
                                                      anim->last_frame->x_offset, anim->last_frame->y_offset);
                        break;
                }

                /* Render next frame */
                composite_frame (anim, link->next->data);
        }

        return anim->last_frame_data;
}

static gboolean
gdk_pixbuf_gif_anim_iter_on_currently_loading_frame (GdkPixbufAnimationIter *anim_iter)
{
        GdkPixbufGifAnimIter *iter;

        iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);

        return iter->current_frame == NULL || iter->current_frame->next == NULL;
}

Coverage Report

Created: 2025-12-08 06:11

Line	Count	Source
1		/* -- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -- */
2		/* GdkPixbuf library - animated gif support
3		*
4		* Copyright (C) 1999 The Free Software Foundation
5		*
6		* Authors: Jonathan Blandford <jrb@redhat.com>
7		* Havoc Pennington <hp@redhat.com>
8		*
9		* This library is free software; you can redistribute it and/or
10		* modify it under the terms of the GNU Lesser General Public
11		* License as published by the Free Software Foundation; either
12		* version 2 of the License, or (at your option) any later version.
13		*
14		* This library is distributed in the hope that it will be useful,
15		* but WITHOUT ANY WARRANTY; without even the implied warranty of
16		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17		* Lesser General Public License for more details.
18		*
19		* You should have received a copy of the GNU Lesser General Public
20		* License along with this library; if not, see <http://www.gnu.org/licenses/>.
21		*/
22
23		#include "config.h"
24		#include <string.h>
25		#include <errno.h>
26		#include "gdk-pixbuf-transform.h"
27		#include "io-gif-animation.h"
28		#include "lzw.h"
29
30		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
31
32		static void gdk_pixbuf_gif_anim_finalize (GObject *object);
33
34		static gboolean gdk_pixbuf_gif_anim_is_static_image (GdkPixbufAnimation *animation);
35		static GdkPixbuf* gdk_pixbuf_gif_anim_get_static_image (GdkPixbufAnimation *animation);
36
37		static void gdk_pixbuf_gif_anim_get_size (GdkPixbufAnimation *anim,
38		int *width,
39		int *height);
40		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
41		static GdkPixbufAnimationIter* gdk_pixbuf_gif_anim_get_iter (GdkPixbufAnimation *anim,
42		const GTimeVal *start_time);
43		G_GNUC_END_IGNORE_DEPRECATIONS
44		static GdkPixbuf* gdk_pixbuf_gif_anim_iter_get_pixbuf (GdkPixbufAnimationIter *iter);
45
46
47
48	0	G_DEFINE_TYPE (GdkPixbufGifAnim, gdk_pixbuf_gif_anim, GDK_TYPE_PIXBUF_ANIMATION);
49	0
50	0	static void
51	0	gdk_pixbuf_gif_anim_init (GdkPixbufGifAnim *anim)
52	0	{
53	0	}
54
55		static void
56		gdk_pixbuf_gif_anim_class_init (GdkPixbufGifAnimClass *klass)
57	0	{
58	0	GObjectClass *object_class = G_OBJECT_CLASS (klass);
59	0	GdkPixbufAnimationClass *anim_class = GDK_PIXBUF_ANIMATION_CLASS (klass);
60
61	0	object_class->finalize = gdk_pixbuf_gif_anim_finalize;
62
63	0	anim_class->is_static_image = gdk_pixbuf_gif_anim_is_static_image;
64	0	anim_class->get_static_image = gdk_pixbuf_gif_anim_get_static_image;
65	0	anim_class->get_size = gdk_pixbuf_gif_anim_get_size;
66	0	anim_class->get_iter = gdk_pixbuf_gif_anim_get_iter;
67	0	}
68
69		static void
70		gdk_pixbuf_gif_anim_finalize (GObject *object)
71	0	{
72	0	GdkPixbufGifAnim *gif_anim = GDK_PIXBUF_GIF_ANIM (object);
73
74	0	GList *l;
75	0	GdkPixbufFrame *frame;
76
77	0	for (l = gif_anim->frames; l; l = l->next) {
78	0	frame = l->data;
79	0	g_byte_array_unref (frame->lzw_data);
80	0	if (frame->color_map_allocated)
81	0	g_free (frame->color_map);
82	0	g_free (frame);
83	0	}
84
85	0	g_list_free (gif_anim->frames);
86
87	0	g_clear_object (&gif_anim->last_frame_data);
88	0	g_clear_object (&gif_anim->last_frame_revert_data);
89
90	0	G_OBJECT_CLASS (gdk_pixbuf_gif_anim_parent_class)->finalize (object);
91	0	}
92
93		static gboolean
94		gdk_pixbuf_gif_anim_is_static_image (GdkPixbufAnimation *animation)
95	0	{
96	0	GdkPixbufGifAnim *gif_anim;
97
98	0	gif_anim = GDK_PIXBUF_GIF_ANIM (animation);
99
100	0	return (gif_anim->frames != NULL &&
101	0	gif_anim->frames->next == NULL);
102	0	}
103
104		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
105		static GdkPixbuf*
106		gdk_pixbuf_gif_anim_get_static_image (GdkPixbufAnimation *animation)
107	0	{
108	0	GdkPixbufGifAnim *gif_anim;
109	0	GdkPixbufAnimationIter *iter;
110	0	GdkPixbuf *pixbuf;
111	0	GTimeVal start_time = { 0, 0 };
112
113	0	gif_anim = GDK_PIXBUF_GIF_ANIM (animation);
114
115	0	if (gif_anim->frames == NULL)
116	0	return NULL;
117
118	0	iter = gdk_pixbuf_gif_anim_get_iter (animation, &start_time);
119	0	pixbuf = gdk_pixbuf_gif_anim_iter_get_pixbuf (iter);
120	0	g_object_unref (iter);
121
122	0	return pixbuf;
123	0	}
124		G_GNUC_END_IGNORE_DEPRECATIONS
125
126		static void
127		gdk_pixbuf_gif_anim_get_size (GdkPixbufAnimation *anim,
128		int *width,
129		int *height)
130	0	{
131	0	GdkPixbufGifAnim *gif_anim;
132
133	0	gif_anim = GDK_PIXBUF_GIF_ANIM (anim);
134
135	0	if (width)
136	0	*width = gif_anim->width;
137
138	0	if (height)
139	0	*height = gif_anim->height;
140	0	}
141
142
143		static void
144		iter_clear (GdkPixbufGifAnimIter *iter)
145	0	{
146	0	iter->current_frame = NULL;
147	0	}
148
149		static void
150		iter_restart (GdkPixbufGifAnimIter *iter)
151	0	{
152	0	iter_clear (iter);
153
154	0	iter->current_frame = iter->gif_anim->frames;
155	0	}
156
157		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
158		static GdkPixbufAnimationIter*
159		gdk_pixbuf_gif_anim_get_iter (GdkPixbufAnimation *anim,
160		const GTimeVal *start_time)
161	0	{
162	0	GdkPixbufGifAnimIter *iter;
163
164	0	iter = g_object_new (GDK_TYPE_PIXBUF_GIF_ANIM_ITER, NULL);
165
166	0	iter->gif_anim = GDK_PIXBUF_GIF_ANIM (anim);
167
168	0	g_object_ref (iter->gif_anim);
169
170	0	iter_restart (iter);
171
172	0	iter->start_time = *start_time;
173	0	iter->current_time = *start_time;
174	0	iter->first_loop_slowness = 0;
175
176	0	return GDK_PIXBUF_ANIMATION_ITER (iter);
177	0	}
178		G_GNUC_END_IGNORE_DEPRECATIONS
179
180
181
182		static void gdk_pixbuf_gif_anim_iter_finalize (GObject *object);
183
184		static int gdk_pixbuf_gif_anim_iter_get_delay_time (GdkPixbufAnimationIter *iter);
185		static gboolean gdk_pixbuf_gif_anim_iter_on_currently_loading_frame (GdkPixbufAnimationIter *iter);
186		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
187		static gboolean gdk_pixbuf_gif_anim_iter_advance (GdkPixbufAnimationIter *iter,
188		const GTimeVal *current_time);
189		G_GNUC_END_IGNORE_DEPRECATIONS
190
191
192
193	0	G_DEFINE_TYPE (GdkPixbufGifAnimIter, gdk_pixbuf_gif_anim_iter, GDK_TYPE_PIXBUF_ANIMATION_ITER);
194	0
195	0	static void
196	0	gdk_pixbuf_gif_anim_iter_init (GdkPixbufGifAnimIter *iter)
197	0	{
198	0	}
199
200		static void
201		gdk_pixbuf_gif_anim_iter_class_init (GdkPixbufGifAnimIterClass *klass)
202	0	{
203	0	GObjectClass *object_class = G_OBJECT_CLASS (klass);
204	0	GdkPixbufAnimationIterClass *anim_iter_class =
205	0	GDK_PIXBUF_ANIMATION_ITER_CLASS (klass);
206
207	0	object_class->finalize = gdk_pixbuf_gif_anim_iter_finalize;
208
209	0	anim_iter_class->get_delay_time = gdk_pixbuf_gif_anim_iter_get_delay_time;
210	0	anim_iter_class->get_pixbuf = gdk_pixbuf_gif_anim_iter_get_pixbuf;
211	0	anim_iter_class->on_currently_loading_frame = gdk_pixbuf_gif_anim_iter_on_currently_loading_frame;
212	0	anim_iter_class->advance = gdk_pixbuf_gif_anim_iter_advance;
213	0	}
214
215		static void
216		gdk_pixbuf_gif_anim_iter_finalize (GObject *object)
217	0	{
218	0	GdkPixbufGifAnimIter *iter = GDK_PIXBUF_GIF_ANIM_ITER (object);
219
220	0	iter_clear (iter);
221
222	0	g_object_unref (iter->gif_anim);
223
224	0	G_OBJECT_CLASS (gdk_pixbuf_gif_anim_iter_parent_class)->finalize (object);
225	0	}
226
227		G_GNUC_BEGIN_IGNORE_DEPRECATIONS
228		static gboolean
229		gdk_pixbuf_gif_anim_iter_advance (GdkPixbufAnimationIter *anim_iter,
230		const GTimeVal *current_time)
231	0	{
232	0	GdkPixbufGifAnimIter *iter;
233	0	gint elapsed;
234	0	gint loop;
235	0	GList *tmp;
236	0	GList *old;
237
238	0	iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);
239
240	0	iter->current_time = *current_time;
241
242		/* We use milliseconds for all times */
243	0	elapsed =
244	0	(((iter->current_time.tv_sec - iter->start_time.tv_sec) * G_USEC_PER_SEC +
245	0	iter->current_time.tv_usec - iter->start_time.tv_usec)) / 1000;
246
247	0	if (elapsed < 0) {
248		/* Try to compensate; probably the system clock
249		* was set backwards
250		*/
251	0	iter->start_time = iter->current_time;
252	0	elapsed = 0;
253	0	}
254
255	0	g_assert (iter->gif_anim->total_time > 0);
256
257		/* See how many times we've already played the full animation,
258		* and subtract time for that.
259		*/
260
261		/* If current_frame is NULL at this point, we have loaded the
262		* animation from a source which fell behind the speed of the
263		* display. We remember how much slower the first loop was due
264		* to this and correct the position calculation in order to not
265		* jump in the middle of the second loop.
266		*/
267	0	if (iter->current_frame == NULL)
268	0	iter->first_loop_slowness = MAX(0, elapsed - iter->gif_anim->total_time);
269
270	0	loop = (elapsed - iter->first_loop_slowness) / iter->gif_anim->total_time;
271	0	elapsed = (elapsed - iter->first_loop_slowness) % iter->gif_anim->total_time;
272
273	0	iter->position = elapsed;
274
275		/* Now move to the proper frame */
276	0	if (iter->gif_anim->loop == 0 \|\| loop < iter->gif_anim->loop)
277	0	tmp = iter->gif_anim->frames;
278	0	else
279	0	tmp = NULL;
280	0	while (tmp != NULL) {
281	0	GdkPixbufFrame *frame = tmp->data;
282
283	0	if (iter->position >= frame->elapsed &&
284	0	iter->position < (frame->elapsed + frame->delay_time))
285	0	break;
286
287	0	tmp = tmp->next;
288	0	}
289
290	0	old = iter->current_frame;
291
292	0	iter->current_frame = tmp;
293
294	0	return iter->current_frame != old;
295	0	}
296		G_GNUC_END_IGNORE_DEPRECATIONS
297
298		int
299		gdk_pixbuf_gif_anim_iter_get_delay_time (GdkPixbufAnimationIter *anim_iter)
300	0	{
301	0	GdkPixbufFrame *frame;
302	0	GdkPixbufGifAnimIter *iter;
303
304	0	iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);
305
306	0	if (iter->current_frame) {
307	0	frame = iter->current_frame->data;
308
309		#if 0
310		g_print ("frame start: %d pos: %d frame len: %d frame remaining: %d\n",
311		frame->elapsed,
312		iter->position,
313		frame->delay_time,
314		frame->delay_time - (iter->position - frame->elapsed));
315		#endif
316
317	0	return frame->delay_time - (iter->position - frame->elapsed);
318	0	} else
319	0	return -1; /* show last frame forever */
320	0	}
321
322		static void
323		composite_frame (GdkPixbufGifAnim anim, GdkPixbufFrame frame)
324	0	{
325	0	LZWDecoder *lzw_decoder = NULL;
326	0	guint8 *index_buffer = NULL;
327	0	gsize n_indexes, i;
328	0	guint16 *interlace_rows = NULL;
329	0	guchar *pixels;
330
331	0	anim->last_frame = frame;
332
333		/* Store overwritten data if required */
334	0	g_clear_object (&anim->last_frame_revert_data);
335	0	if (frame->action == GDK_PIXBUF_FRAME_REVERT) {
336	0	anim->last_frame_revert_data = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, frame->width, frame->height);
337	0	if (anim->last_frame_revert_data != NULL)
338	0	gdk_pixbuf_copy_area (anim->last_frame_data,
339	0	frame->x_offset, frame->y_offset, frame->width, frame->height,
340	0	anim->last_frame_revert_data,
341	0	0, 0);
342	0	}
343
344	0	lzw_decoder = lzw_decoder_new (frame->lzw_code_size + 1);
345	0	index_buffer = g_new (guint8, frame->width * frame->height);
346	0	if (index_buffer == NULL)
347	0	goto out;
348
349	0	interlace_rows = g_new (guint16, frame->height);
350	0	if (interlace_rows == NULL)
351	0	goto out;
352	0	if (frame->interlace) {
353	0	int row, n = 0;
354	0	for (row = 0; row < frame->height; row += 8)
355	0	interlace_rows[n++] = row;
356	0	for (row = 4; row < frame->height; row += 8)
357	0	interlace_rows[n++] = row;
358	0	for (row = 2; row < frame->height; row += 4)
359	0	interlace_rows[n++] = row;
360	0	for (row = 1; row < frame->height; row += 2)
361	0	interlace_rows[n++] = row;
362	0	}
363	0	else {
364	0	int row;
365	0	for (row = 0; row < frame->height; row++)
366	0	interlace_rows[row] = row;
367	0	}
368
369	0	n_indexes = lzw_decoder_feed (lzw_decoder, frame->lzw_data->data, frame->lzw_data->len, index_buffer, frame->width * frame->height);
370	0	pixels = gdk_pixbuf_get_pixels (anim->last_frame_data);
371	0	for (i = 0; i < n_indexes; i++) {
372	0	guint8 index = index_buffer[i];
373	0	guint x, y;
374	0	gsize offset;
375
376	0	if (index == frame->transparent_index)
377	0	continue;
378
379	0	x = i % frame->width + frame->x_offset;
380	0	y = interlace_rows[i / frame->width] + frame->y_offset;
381	0	if (x >= anim->width \|\| y >= anim->height)
382	0	continue;
383
384	0	if (g_size_checked_mul (&offset, gdk_pixbuf_get_rowstride (anim->last_frame_data), y) &&
385	0	g_size_checked_add (&offset, offset, x * 4)) {
386	0	pixels[offset + 0] = frame->color_map[index * 3 + 0];
387	0	pixels[offset + 1] = frame->color_map[index * 3 + 1];
388	0	pixels[offset + 2] = frame->color_map[index * 3 + 2];
389	0	pixels[offset + 3] = 255;
390	0	}
391	0	}
392
393	0	out:
394	0	g_clear_object (&lzw_decoder);
395	0	g_free (index_buffer);
396	0	g_free (interlace_rows);
397	0	}
398
399		GdkPixbuf*
400		gdk_pixbuf_gif_anim_iter_get_pixbuf (GdkPixbufAnimationIter *anim_iter)
401	0	{
402	0	GdkPixbufGifAnimIter *iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);
403	0	GdkPixbufGifAnim *anim = iter->gif_anim;
404	0	GdkPixbufFrame *requested_frame;
405	0	GList *link;
406
407	0	if (iter->current_frame != NULL)
408	0	requested_frame = iter->current_frame->data;
409	0	else
410	0	requested_frame = g_list_last (anim->frames)->data;
411
412		/* If the previously rendered frame is not before this one, then throw it away */
413	0	if (anim->last_frame != NULL) {
414	0	link = g_list_find (anim->frames, anim->last_frame);
415	0	while (link != NULL && link->data != requested_frame)
416	0	link = link->next;
417	0	if (link == NULL)
418	0	anim->last_frame = NULL;
419	0	}
420
421		/* If no rendered frame, render the first frame */
422	0	if (anim->last_frame == NULL) {
423	0	gsize len = 0;
424	0	if (anim->last_frame_data == NULL)
425	0	anim->last_frame_data = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, anim->width, anim->height);
426	0	if (anim->last_frame_data == NULL)
427	0	return NULL;
428	0	if (g_size_checked_mul (&len, gdk_pixbuf_get_rowstride (anim->last_frame_data), anim->height))
429	0	memset (gdk_pixbuf_get_pixels (anim->last_frame_data), 0, len);
430	0	else
431	0	return NULL;
432	0	composite_frame (anim, g_list_nth_data (anim->frames, 0));
433	0	}
434
435		/* If the requested frame is already rendered, then no action required */
436	0	if (requested_frame == anim->last_frame)
437	0	return anim->last_frame_data;
438
439		/* Starting from the last rendered frame, render to the current frame */
440	0	for (link = g_list_find (anim->frames, anim->last_frame); link->next != NULL && link->data != requested_frame; link = link->next) {
441	0	GdkPixbufFrame *frame = link->data;
442	0	guchar *pixels;
443	0	int y, x_end, y_end;
444
445		/* Remove last frame if required */
446	0	switch (frame->action) {
447	0	case GDK_PIXBUF_FRAME_RETAIN:
448	0	break;
449	0	case GDK_PIXBUF_FRAME_DISPOSE:
450		/* Replace previous area with background */
451	0	pixels = gdk_pixbuf_get_pixels (anim->last_frame_data);
452	0	x_end = MIN (anim->last_frame->x_offset + anim->last_frame->width, anim->width);
453	0	y_end = MIN (anim->last_frame->y_offset + anim->last_frame->height, anim->height);
454	0	for (y = anim->last_frame->y_offset; y < y_end; y++) {
455	0	gsize offset;
456	0	if (g_size_checked_mul (&offset, gdk_pixbuf_get_rowstride (anim->last_frame_data), y) &&
457	0	g_size_checked_add (&offset, offset, anim->last_frame->x_offset * 4)) {
458	0	memset (pixels + offset, 0, (x_end - anim->last_frame->x_offset) * 4);
459	0	}
460	0	}
461	0	break;
462	0	case GDK_PIXBUF_FRAME_REVERT:
463		/* Replace previous area with last retained area */
464	0	if (anim->last_frame_revert_data != NULL)
465	0	gdk_pixbuf_copy_area (anim->last_frame_revert_data,
466	0	0, 0, anim->last_frame->width, anim->last_frame->height,
467	0	anim->last_frame_data,
468	0	anim->last_frame->x_offset, anim->last_frame->y_offset);
469	0	break;
470	0	}
471
472		/* Render next frame */
473	0	composite_frame (anim, link->next->data);
474	0	}
475
476	0	return anim->last_frame_data;
477	0	}
478
479		static gboolean
480		gdk_pixbuf_gif_anim_iter_on_currently_loading_frame (GdkPixbufAnimationIter *anim_iter)
481	0	{
482	0	GdkPixbufGifAnimIter *iter;
483
484	0	iter = GDK_PIXBUF_GIF_ANIM_ITER (anim_iter);
485
486	0	return iter->current_frame == NULL \|\| iter->current_frame->next == NULL;
487	0	}