swfdec/swfdec_audio_decoder_uncompressed.c

   1 /* Swfdec
   2  * Copyright (C) 2006-2008 Benjamin Otte <otte@gnome.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "swfdec_audio_decoder_uncompressed.h"
  25 #include "swfdec_debug.h"
  26 #include "swfdec_internal.h"
  27
  28 G_DEFINE_TYPE (SwfdecAudioDecoderUncompressed, swfdec_audio_decoder_uncompressed, SWFDEC_TYPE_AUDIO_DECODER)
  29
  30 static gboolean
  31 swfdec_audio_decoder_uncompressed_prepare (guint codec, SwfdecAudioFormat format, char **missing)
  32 {
  33   return codec == SWFDEC_AUDIO_CODEC_UNDEFINED ||
  34       codec == SWFDEC_AUDIO_CODEC_UNCOMPRESSED;
  35 }
  36
  37 static SwfdecAudioDecoder *
  38 swfdec_audio_decoder_uncompressed_create (guint codec, SwfdecAudioFormat format)
  39 {
  40   if (codec != SWFDEC_AUDIO_CODEC_UNDEFINED &&
  41       codec != SWFDEC_AUDIO_CODEC_UNCOMPRESSED)
  42     return NULL;
  43
  44   return g_object_new (SWFDEC_TYPE_AUDIO_DECODER_UNCOMPRESSED, NULL);
  45 }
  46
  47 static SwfdecBuffer *
  48 swfdec_audio_decoder_uncompressed_upscale (SwfdecBuffer *buffer, SwfdecAudioFormat format)
  49 {
  50   guint channels = swfdec_audio_format_get_channels (format);
  51   guint granularity = swfdec_audio_format_get_granularity (format);
  52   SwfdecBuffer *ret;
  53   guint i, j, n_samples;
  54   gint16 *src, *dest;
  55
  56   n_samples = buffer->length / 2 / channels;
  57   if (n_samples * 2 * channels != buffer->length) {
  58     SWFDEC_ERROR ("incorrect buffer size, %"G_GSIZE_FORMAT" bytes overhead",
  59         buffer->length - n_samples * 2 * channels);
  60   }
  61   ret = swfdec_buffer_new (n_samples * 4 * granularity);
  62   /* can be upscaled, because the input buffer and the newly allocated buffer
  63    * are aligned properly */
  64   src = (gint16 *) (gpointer) buffer->data;
  65   dest = (gint16 *) (gpointer) ret->data;
  66   for (i = 0; i < n_samples; i++) {
  67     for (j = 0; j < granularity; j++) {
  68       *dest++ = src[0];
  69       *dest++ = src[channels - 1];
  70     }
  71     src += channels;
  72   }
  73
  74   swfdec_buffer_unref (buffer);
  75   return ret;
  76 }
  77
  78 static SwfdecBuffer *
  79 swfdec_audio_decoder_uncompressed_decode_8bit (SwfdecBuffer *buffer)
  80 {
  81   SwfdecBuffer *ret;
  82   gint16 *out;
  83   guint8 *in;
  84   guint i;
  85
  86   ret = swfdec_buffer_new (buffer->length * 2);
  87   out = (gint16 *) (void *) ret->data;
  88   in = buffer->data;
  89   for (i = 0; i < buffer->length; i++) {
  90     *out = ((gint16) *in << 8) ^ (-1);
  91     out++;
  92     in++;
  93   }
  94   return ret;
  95 }
  96
  97 static SwfdecBuffer *
  98 swfdec_audio_decoder_uncompressed_decode_16bit (SwfdecBuffer *buffer)
  99 {
 100   SwfdecBuffer *ret;
 101   SwfdecBits bits;
 102   gint16 *dest;
 103   guint i;
 104
 105   if (buffer->length & 2) {
 106     SWFDEC_ERROR ("buffer length not a multiple of 16bit");
 107   }
 108   ret = swfdec_buffer_new (buffer->length & ~1);
 109   swfdec_bits_init (&bits, buffer);
 110   dest = (gint16 *) (gpointer) ret->data;
 111   for (i = 0; i < ret->length; i += 2) {
 112     *dest = swfdec_bits_get_u16 (&bits);
 113     dest++;
 114   }
 115
 116   return ret;
 117 }
 118
 119 static void
 120 swfdec_audio_decoder_uncompressed_push (SwfdecAudioDecoder *decoder,
 121     SwfdecBuffer *buffer)
 122 {
 123   SwfdecBuffer *tmp;
 124
 125   if (buffer == NULL)
 126     return;
 127
 128   if (swfdec_audio_format_is_16bit (decoder->format))
 129     tmp = swfdec_audio_decoder_uncompressed_decode_16bit (buffer);
 130   else
 131     tmp = swfdec_audio_decoder_uncompressed_decode_8bit (buffer);
 132
 133   tmp = swfdec_audio_decoder_uncompressed_upscale (tmp, decoder->format);
 134   swfdec_buffer_queue_push (SWFDEC_AUDIO_DECODER_UNCOMPRESSED (decoder)->queue,
 135       tmp);
 136 }
 137
 138 static SwfdecBuffer *
 139 swfdec_audio_decoder_uncompressed_pull (SwfdecAudioDecoder *decoder)
 140 {
 141   SwfdecAudioDecoderUncompressed *dec = (SwfdecAudioDecoderUncompressed *) decoder;
 142
 143   return swfdec_buffer_queue_pull_buffer (dec->queue);
 144 }
 145
 146 static void
 147 swfdec_audio_decoder_uncompressed_dispose (GObject *object)
 148 {
 149   SwfdecAudioDecoderUncompressed *dec = (SwfdecAudioDecoderUncompressed *) object;
 150
 151   swfdec_buffer_queue_unref (dec->queue);
 152
 153   G_OBJECT_CLASS (swfdec_audio_decoder_uncompressed_parent_class)->dispose (object);
 154 }
 155
 156 static void
 157 swfdec_audio_decoder_uncompressed_class_init (SwfdecAudioDecoderUncompressedClass *klass)
 158 {
 159   GObjectClass *object_class = G_OBJECT_CLASS (klass);
 160   SwfdecAudioDecoderClass *decoder_class = SWFDEC_AUDIO_DECODER_CLASS (klass);
 161
 162   object_class->dispose = swfdec_audio_decoder_uncompressed_dispose;
 163
 164   decoder_class->prepare = swfdec_audio_decoder_uncompressed_prepare;
 165   decoder_class->create = swfdec_audio_decoder_uncompressed_create;
 166   decoder_class->pull = swfdec_audio_decoder_uncompressed_pull;
 167   decoder_class->push = swfdec_audio_decoder_uncompressed_push;
 168 }
 169
 170 static void
 171 swfdec_audio_decoder_uncompressed_init (SwfdecAudioDecoderUncompressed *dec)
 172 {
 173   dec->queue = swfdec_buffer_queue_new ();
 174 }
 175