swfdec_video.c

Swfdec is a decoder/renderer for Macromedia Flash animations. The decoding and rendering engine is

/* Swfdec
 * Copyright (C) 2007 Benjamin Otte <[e-mail]>
 *
 * 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 2.1 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, 
 * Boston, MA  02110-1301  USA
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdlib.h>

#include "swfdec_video.h"
#include "swfdec_debug.h"
#include "swfdec_font.h"
#include "swfdec_swf_decoder.h"
#include "swfdec_video_movie.h"

typedef struct {
  guint			frame;
  SwfdecBuffer *	buffer;
} SwfdecVideoTag;

static int
swfdec_video_compare_frame (gconstpointer a, gconstpointer b)
{
  return (int) *((const guint *) a) - *((const guint *) b);
}

static SwfdecBuffer *
swfdec_video_find_frame (SwfdecVideo *video, guint frame)
{
  SwfdecVideoTag tmp = { frame, NULL };
  SwfdecVideoTag *tag;

  if (video->images->len == 0)
    return NULL;

  tag = bsearch (&tmp, video->images->data, video->images->len,
      sizeof (SwfdecVideoTag), swfdec_video_compare_frame);

  return tag ? tag->buffer : NULL;
}

/*** INPUT FOR MOVIE ***/

typedef struct {
  SwfdecVideoMovieInput	input;
  SwfdecVideoMovie *	movie;
  SwfdecVideo *		video;
  gpointer		decoder;
  guint			current_frame;
} SwfdecVideoInput;

static void
swfdec_video_input_iterate (SwfdecVideoMovieInput *input_)
{
  SwfdecVideoInput *input = (SwfdecVideoInput *) input_;
  SwfdecBuffer *buffer;
  cairo_surface_t *surface;

  input->current_frame = (input->current_frame + 1) % input->video->n_frames;
  if (input->decoder == NULL)
    return;
  buffer = swfdec_video_find_frame (input->video, input->current_frame);
  if (buffer == NULL)
    return;

  surface = swfdec_video_decoder_decode (input->decoder, buffer);
  swfdec_video_movie_new_image (input->movie, surface);
  cairo_surface_destroy (surface);
}

static void
swfdec_video_input_connect (SwfdecVideoMovieInput *input_, SwfdecVideoMovie *movie)
{
  SwfdecVideoInput *input = (SwfdecVideoInput *) input_;

  g_assert (input->movie == NULL);
  input->movie = movie;
}

static void
swfdec_video_input_disconnect (SwfdecVideoMovieInput *input_, SwfdecVideoMovie *movie)
{
  SwfdecVideoInput *input = (SwfdecVideoInput *) input_;

  g_assert (input->movie == movie);
  if (input->decoder)
    swfdec_video_decoder_free (input->decoder);
  g_object_unref (input->video);
  g_free (input);
}

static SwfdecVideoMovieInput *
swfdec_video_input_new (SwfdecVideo *video)
{
  SwfdecVideoInput *input;
  
  if (video->n_frames == 0)
    return NULL;
  input = g_new0 (SwfdecVideoInput, 1);
  input->decoder = swfdec_video_decoder_new (video->format);
  if (input->decoder == NULL) {
    g_free (input);
    return NULL;
  }
  input->input.connect = swfdec_video_input_connect;
  input->input.iterate = swfdec_video_input_iterate;
  input->input.disconnect = swfdec_video_input_disconnect;
  g_object_ref (video);
  input->video = video;
  input->current_frame = (guint) -1;
  return &input->input;
}

/*** SWFDEC_VIDEO ***/

G_DEFINE_TYPE (SwfdecVideo, swfdec_video, SWFDEC_TYPE_GRAPHIC)

static SwfdecMovie *
swfdec_video_create_movie (SwfdecGraphic *graphic, gsize *size)
{
  SwfdecVideo *video = SWFDEC_VIDEO (graphic);
  SwfdecVideoMovie *movie = g_object_new (SWFDEC_TYPE_VIDEO_MOVIE, NULL);
  SwfdecVideoMovieInput *input = swfdec_video_input_new (video);

  movie->video = SWFDEC_VIDEO (graphic);
  g_object_ref (graphic);
  if (input)
    swfdec_video_movie_set_input (movie, input);
  *size = sizeof (SwfdecVideoMovie);
  return SWFDEC_MOVIE (movie);
}

static void
swfdec_video_dispose (GObject *object)
{
  SwfdecVideo * video = SWFDEC_VIDEO (object);
  guint i;

  for (i = 0; i < video->images->len; i++) {
    swfdec_buffer_unref (g_array_index (video->images, SwfdecVideoTag, i).buffer);
  }
  g_array_free (video->images, TRUE);
  G_OBJECT_CLASS (swfdec_video_parent_class)->dispose (object);
}

static void
swfdec_video_class_init (SwfdecVideoClass * g_class)
{
  GObjectClass *object_class = G_OBJECT_CLASS (g_class);
  SwfdecGraphicClass *graphic_class = SWFDEC_GRAPHIC_CLASS (g_class);

  object_class->dispose = swfdec_video_dispose;

  graphic_class->create_movie = swfdec_video_create_movie;
}

static void
swfdec_video_init (SwfdecVideo * video)
{
  video->images = g_array_new (FALSE, FALSE, sizeof (SwfdecVideoTag));
}

int
tag_func_define_video (SwfdecSwfDecoder *s, guint tag)
{
  SwfdecVideo *video;
  guint id;
  SwfdecBits *bits = &s->b;
  int smoothing, deblocking;

  id = swfdec_bits_get_u16 (bits);
  video = swfdec_swf_decoder_create_character (s, id, SWFDEC_TYPE_VIDEO);
  if (!video)
    return SWFDEC_STATUS_OK;
  
  video->n_frames = swfdec_bits_get_u16 (bits);
  video->width = swfdec_bits_get_u16 (bits);
  video->height = swfdec_bits_get_u16 (bits);
  swfdec_bits_getbits (bits, 4);
  deblocking = swfdec_bits_getbits (bits, 3);
  smoothing = swfdec_bits_getbit (bits);
  video->format = swfdec_bits_get_u8 (bits);
  SWFDEC_LOG ("  frames: %u", video->n_frames);
  SWFDEC_LOG ("  size: %ux%u", video->width, video->height);
  SWFDEC_LOG ("  deblocking: %d", deblocking);
  SWFDEC_LOG ("  smoothing: %d", smoothing);
  SWFDEC_LOG ("  format: %d", (int) video->format);
  return SWFDEC_STATUS_OK;
}

int
tag_func_video_frame (SwfdecSwfDecoder *s, guint unused_tag)
{
  SwfdecVideo *video;
  guint id;
  SwfdecVideoTag tag;

  id = swfdec_bits_get_u16 (&s->b);
  video = (SwfdecVideo *) swfdec_swf_decoder_get_character (s, id);
  if (!SWFDEC_IS_VIDEO (video)) {
    SWFDEC_ERROR ("id %u does not reference a video object", id);
    return SWFDEC_STATUS_OK;
  }
  tag.frame = swfdec_bits_get_u16 (&s->b);
  if (tag.frame >= video->n_frames) {
    SWFDEC_ERROR ("frame %u out of range %u", tag.frame, video->n_frames);
    return SWFDEC_STATUS_OK;
  }
  /* it seems flash video saves keyframe + format in every frame - 
   * at least libflv + ming does that and Flash Player plays it.
   */
  if (video->format == SWFDEC_VIDEO_FORMAT_SCREEN) {
#if 0
    keyframe = swfdec_bits_get_bits (&s->b, 4);
    format = swfdec_bits_get_bits (&s->b, 4);
#endif
    swfdec_bits_get_u8 (&s->b);
  }
  tag.buffer = swfdec_bits_get_buffer (&s->b, -1);
  if (tag.buffer == NULL) {
    SWFDEC_WARNING ("no buffer, ignoring");
    return SWFDEC_STATUS_OK;
  }
  if (video->images->len == 0) {
    g_array_append_val (video->images, tag);
  } else if (g_array_index (video->images, SwfdecVideoTag, video->images->len - 1).frame < tag.frame) {
    g_array_append_val (video->images, tag);
  } else {
    guint i;
    SWFDEC_WARNING ("frame not in ascending order (last is %u, this is %u)",
	g_array_index (video->images, SwfdecVideoTag, video->images->len - 1).frame, tag.frame);
    for (i = 0; i < video->images->len; i++) {
      SwfdecVideoTag *cur = &g_array_index (video->images, SwfdecVideoTag, i);
      if (cur->frame < tag.frame)
	continue;
      if (cur->frame == tag.frame) {
	SWFDEC_ERROR ("duplicate frame id %u", cur->frame);
	continue;
      }
      g_array_insert_val (video->images, i, tag);
      break;
    }
    if (i >= video->images->len)
      g_array_append_val (video->images, tag);
  }
  return SWFDEC_STATUS_OK;
}