complete AVS playback system (from Creature Shock computer game),

courtesy of Aurelien Jacobs <aurel at gnuage dot org>

Originally committed as revision 5028 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 238 insertions, 0 deletions

diff --git a/libavformat/avs.c b/libavformat/avs.c
new file mode 100644
index 0000000000..684860b11a
--- /dev/null
+++ b/libavformat/avs.c
@@ -0,0 +1,238 @@
+/*
+ * AVS demuxer.
+ * Copyright (c) 2006  Aurelien Jacobs <aurel@gnuage.org>
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "avformat.h"
+#include "voc.h"
+
+
+typedef struct avs_format {
+    voc_dec_context_t voc;
+    AVStream *st_video;
+    AVStream *st_audio;
+    int width;
+    int height;
+    int bits_per_sample;
+    int fps;
+    int nb_frames;
+    int remaining_frame_size;
+    int remaining_audio_size;
+} avs_format_t;
+
+typedef enum avs_block_type {
+    AVS_VIDEO     = 0x01,
+    AVS_AUDIO     = 0x02,
+    AVS_PALETTE   = 0x03,
+    AVS_GAME_DATA = 0x04,
+} avs_block_type_t;
+
+
+#ifdef CONFIG_DEMUXERS
+
+static int avs_probe(AVProbeData * p)
+{
+    const uint8_t *d;
+
+    if (p->buf_size < 2)
+        return 0;
+    d = p->buf;
+    if (d[0] == 'w' && d[1] == 'W' && d[2] == 0x10 && d[3] == 0)
+        return 50;
+
+    return 0;
+}
+
+static int avs_read_header(AVFormatContext * s, AVFormatParameters * ap)
+{
+    avs_format_t *avs = s->priv_data;
+
+    s->ctx_flags |= AVFMTCTX_NOHEADER;
+
+    url_fskip(&s->pb, 4);
+    avs->width = get_le16(&s->pb);
+    avs->height = get_le16(&s->pb);
+    avs->bits_per_sample = get_le16(&s->pb);
+    avs->fps = get_le16(&s->pb);
+    avs->nb_frames = get_le32(&s->pb);
+    avs->remaining_frame_size = 0;
+    avs->remaining_audio_size = 0;
+
+    avs->st_video = avs->st_audio = NULL;
+
+    if (avs->width != 318 || avs->height != 198)
+        av_log(s, AV_LOG_ERROR, "This avs pretend to be %dx%d "
+               "when the avs format is supposed to be 318x198 only.\n",
+               avs->width, avs->height);
+
+    return 0;
+}
+
+static int
+avs_read_video_packet(AVFormatContext * s, AVPacket * pkt,
+                      avs_block_type_t type, int sub_type, int size,
+                      uint8_t * palette, int palette_size)
+{
+    avs_format_t *avs = s->priv_data;
+    int ret;
+
+    ret = av_new_packet(pkt, size + palette_size);
+    if (ret < 0)
+        return ret;
+
+    if (palette_size) {
+        pkt->data[0] = 0x00;
+        pkt->data[1] = 0x03;
+        pkt->data[2] = palette_size & 0xFF;
+        pkt->data[3] = (palette_size >> 8) & 0xFF;
+        memcpy(pkt->data + 4, palette, palette_size - 4);
+    }
+
+    pkt->data[palette_size + 0] = sub_type;
+    pkt->data[palette_size + 1] = type;
+    pkt->data[palette_size + 2] = size & 0xFF;
+    pkt->data[palette_size + 3] = (size >> 8) & 0xFF;
+    ret = get_buffer(&s->pb, pkt->data + palette_size + 4, size - 4) + 4;
+    if (ret < size) {
+        av_free_packet(pkt);
+        return AVERROR_IO;
+    }
+
+    pkt->size = ret + palette_size;
+    pkt->stream_index = avs->st_video->index;
+    if (sub_type == 0)
+        pkt->flags |= PKT_FLAG_KEY;
+
+    return 0;
+}
+
+static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
+{
+    avs_format_t *avs = s->priv_data;
+    int ret, size;
+
+    size = url_ftell(&s->pb);
+    ret = voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
+    size = url_ftell(&s->pb) - size;
+    avs->remaining_audio_size -= size;
+
+    if (ret == AVERROR_IO)
+        return 0;    /* this indicate EOS */
+    if (ret < 0)
+        return ret;
+
+    pkt->stream_index = avs->st_audio->index;
+    pkt->flags |= PKT_FLAG_KEY;
+
+    return size;
+}
+
+static int avs_read_packet(AVFormatContext * s, AVPacket * pkt)
+{
+    avs_format_t *avs = s->priv_data;
+    int sub_type = 0, size = 0;
+    avs_block_type_t type = 0;
+    int palette_size = 0;
+    uint8_t palette[4 + 3 * 256];
+    int ret;
+
+    if (avs->remaining_audio_size > 0)
+        if (avs_read_audio_packet(s, pkt) > 0)
+            return 0;
+
+    while (1) {
+        if (avs->remaining_frame_size <= 0) {
+            if (!get_le16(&s->pb))    /* found EOF */
+                return AVERROR_IO;
+            avs->remaining_frame_size = get_le16(&s->pb) - 4;
+        }
+
+        while (avs->remaining_frame_size > 0) {
+            sub_type = get_byte(&s->pb);
+            type = get_byte(&s->pb);
+            size = get_le16(&s->pb);
+            avs->remaining_frame_size -= size;
+
+            switch (type) {
+            case AVS_PALETTE:
+                ret = get_buffer(&s->pb, palette, size - 4);
+                if (ret < size - 4)
+                    return AVERROR_IO;
+                palette_size = size;
+                break;
+
+            case AVS_VIDEO:
+                if (!avs->st_video) {
+                    avs->st_video = av_new_stream(s, AVS_VIDEO);
+                    if (avs->st_video == NULL)
+                        return AVERROR_NOMEM;
+                    avs->st_video->codec->codec_type = CODEC_TYPE_VIDEO;
+                    avs->st_video->codec->codec_id = CODEC_ID_AVS;
+                    avs->st_video->codec->width = avs->width;
+                    avs->st_video->codec->height = avs->height;
+                    avs->st_video->codec->bits_per_sample=avs->bits_per_sample;
+                    avs->st_video->nb_frames = avs->nb_frames;
+                    avs->st_video->codec->time_base = (AVRational) {
+                    1, avs->fps};
+                }
+                return avs_read_video_packet(s, pkt, type, sub_type, size,
+                                             palette, palette_size);
+
+            case AVS_AUDIO:
+                if (!avs->st_audio) {
+                    avs->st_audio = av_new_stream(s, AVS_AUDIO);
+                    if (avs->st_audio == NULL)
+                        return AVERROR_NOMEM;
+                    avs->st_audio->codec->codec_type = CODEC_TYPE_AUDIO;
+                }
+                avs->remaining_audio_size = size - 4;
+                size = avs_read_audio_packet(s, pkt);
+                if (size != 0)
+                    return size;
+                break;
+
+            default:
+                url_fskip(&s->pb, size - 4);
+            }
+        }
+    }
+}
+
+static int avs_read_close(AVFormatContext * s)
+{
+    return 0;
+}
+
+static AVInputFormat avs_iformat = {
+    "avs",
+    "avs format",
+    sizeof(avs_format_t),
+    avs_probe,
+    avs_read_header,
+    avs_read_packet,
+    avs_read_close,
+};
+
+#endif /* CONFIG_DEMUXERS */
+
+int avs_init(void)
+{
+#ifdef CONFIG_DEMUXERS
+    av_register_input_format(&avs_iformat);
+#endif /* CONFIG_DEMUXERS */
+    return 0;
+}