BMV demuxer and decoder

Signed-off-by: Martin Storsjö <martin@martin.st>

1 files changed, 136 insertions, 0 deletions

diff --git a/libavformat/bmv.c b/libavformat/bmv.c
new file mode 100644
index 0000000000..fb41712868
--- /dev/null
+++ b/libavformat/bmv.c
@@ -0,0 +1,136 @@
+/*
+ * Discworld II BMV demuxer
+ * Copyright (c) 2011 Konstantin Shishkov.
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+
+enum BMVFlags {
+    BMV_NOP = 0,
+    BMV_END,
+    BMV_DELTA,
+    BMV_INTRA,
+
+    BMV_AUDIO   = 0x20,
+};
+
+typedef struct BMVContext {
+    uint8_t *packet;
+    int      size;
+    int      get_next;
+    int64_t  audio_pos;
+} BMVContext;
+
+static int bmv_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    AVStream *st, *ast;
+    BMVContext *c = s->priv_data;
+
+    st = avformat_new_stream(s, 0);
+    if (!st)
+        return AVERROR(ENOMEM);
+    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+    st->codec->codec_id   = CODEC_ID_BMV_VIDEO;
+    st->codec->width      = 640;
+    st->codec->height     = 429;
+    st->codec->pix_fmt    = PIX_FMT_PAL8;
+    av_set_pts_info(st, 16, 1, 12);
+    ast = avformat_new_stream(s, 0);
+    if (!ast)
+        return AVERROR(ENOMEM);
+    ast->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
+    ast->codec->codec_id        = CODEC_ID_BMV_AUDIO;
+    ast->codec->channels        = 2;
+    ast->codec->sample_rate     = 22050;
+    av_set_pts_info(ast, 16, 1, 22050);
+
+    c->get_next  = 1;
+    c->audio_pos = 0;
+    return 0;
+}
+
+static int bmv_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    BMVContext *c = s->priv_data;
+    int type;
+    void *tmp;
+
+    while (c->get_next) {
+        if (s->pb->eof_reached)
+            return AVERROR_EOF;
+        type = avio_r8(s->pb);
+        if (type == BMV_NOP)
+            continue;
+        if (type == BMV_END)
+            return AVERROR_EOF;
+        c->size = avio_rl24(s->pb);
+        if (!c->size)
+            return AVERROR_INVALIDDATA;
+        tmp = av_realloc(c->packet, c->size + 1);
+        if (!tmp)
+            return AVERROR(ENOMEM);
+        c->packet = tmp;
+        c->packet[0] = type;
+        if (avio_read(s->pb, c->packet + 1, c->size) != c->size)
+            return AVERROR(EIO);
+        if (type & BMV_AUDIO) {
+            int audio_size = c->packet[1] * 65 + 1;
+            if (audio_size >= c->size) {
+                av_log(s, AV_LOG_ERROR, "Reported audio size %d is bigger than packet size (%d)\n",
+                       audio_size, c->size);
+                return AVERROR_INVALIDDATA;
+            }
+            if (av_new_packet(pkt, audio_size) < 0)
+                return AVERROR(ENOMEM);
+            memcpy(pkt->data, c->packet + 1, pkt->size);
+            pkt->stream_index = 1;
+            pkt->pts          = c->audio_pos;
+            pkt->duration     = c->packet[1] * 32;
+            c->audio_pos += pkt->duration;
+            c->get_next   = 0;
+            return pkt->size;
+        } else
+            break;
+    }
+    if (av_new_packet(pkt, c->size + 1) < 0)
+        return AVERROR(ENOMEM);
+    pkt->stream_index = 0;
+    c->get_next = 1;
+    memcpy(pkt->data, c->packet, pkt->size);
+    return pkt->size;
+}
+
+static int bmv_read_close(AVFormatContext *s)
+{
+    BMVContext *c = s->priv_data;
+
+    av_freep(&c->packet);
+
+    return 0;
+}
+
+AVInputFormat ff_bmv_demuxer = {
+    .name           = "bmv",
+    .long_name      = NULL_IF_CONFIG_SMALL("Discworld II BMV"),
+    .priv_data_size = sizeof(BMVContext),
+    .read_header    = bmv_read_header,
+    .read_packet    = bmv_read_packet,
+    .read_close     = bmv_read_close,
+    .extensions     = "bmv"
+};