Initial revision

Originally committed as revision 5 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 257 insertions, 0 deletions

diff --git a/libav/avidec.c b/libav/avidec.c
new file mode 100644
index 0000000000..ec90565feb
--- /dev/null
+++ b/libav/avidec.c
@@ -0,0 +1,257 @@
+/*
+ * AVI decoder.
+ * Copyright (c) 2001 Gerard Lantau.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <errno.h>
+
+#include "avformat.h"
+#include "avi.h"
+
+//#define DEBUG
+
+typedef struct AVIIndex {
+    unsigned char tag[4];
+    unsigned int flags, pos, len;
+    struct AVIIndex *next;
+} AVIIndex;
+
+typedef struct {
+    INT64 movi_end;
+    offset_t movi_list;
+    AVIIndex *first, *last;
+} AVIContext;
+
+#ifdef DEBUG
+void print_tag(const char *str, unsigned int tag, int size)
+{
+    printf("%s: tag=%c%c%c%c size=0x%x\n",
+           str, tag & 0xff,
+           (tag >> 8) & 0xff,
+           (tag >> 16) & 0xff,
+           (tag >> 24) & 0xff,
+           size);
+}
+#endif
+
+int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    AVIContext *avi;
+    ByteIOContext *pb = &s->pb;
+    UINT32 tag, tag1;
+    int codec_type, stream_index, size, frame_period, bit_rate;
+    int i;
+    AVStream *st;
+
+    avi = malloc(sizeof(AVIContext));
+    if (!avi)
+        return -1;
+    memset(avi, 0, sizeof(AVIContext));
+    s->priv_data = avi;
+
+    /* check RIFF header */
+    tag = get_le32(pb);
+
+    if (tag != MKTAG('R', 'I', 'F', 'F'))
+        return -1;
+    get_le32(pb); /* file size */
+    tag = get_le32(pb);
+    if (tag != MKTAG('A', 'V', 'I', ' '))
+        return -1;
+    
+    /* first list tag */
+    stream_index = -1;
+    codec_type = -1;
+    frame_period = 0;
+    for(;;) {
+        if (url_feof(pb))
+            goto fail;
+        tag = get_le32(pb);
+        size = get_le32(pb);
+#ifdef DEBUG
+        print_tag("tag", tag, size);
+#endif
+
+        switch(tag) {
+        case MKTAG('L', 'I', 'S', 'T'):
+            /* ignored, except when start of video packets */
+            tag1 = get_le32(pb);
+#ifdef DEBUG
+            print_tag("list", tag1, 0);
+#endif
+            if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
+                avi->movi_end = url_ftell(pb) + size - 4;
+#ifdef DEBUG
+                printf("movi end=%Lx\n", avi->movi_end);
+#endif
+                goto end_of_header;
+            }
+            break;
+        case MKTAG('a', 'v', 'i', 'h'):
+            /* avi header */
+            frame_period = get_le32(pb);
+            bit_rate = get_le32(pb) * 8;
+            url_fskip(pb, 4 * 4);
+            s->nb_streams = get_le32(pb);
+            for(i=0;i<s->nb_streams;i++) {
+                AVStream *st;
+                st = malloc(sizeof(AVStream));
+                if (!st)
+                    goto fail;
+                memset(st, 0, sizeof(AVStream));
+                s->streams[i] = st;
+            }
+            url_fskip(pb, size - 7 * 4);
+            break;
+        case MKTAG('s', 't', 'r', 'h'):
+            /* stream header */
+            stream_index++;
+            tag1 = get_le32(pb);
+            switch(tag1) {
+            case MKTAG('v', 'i', 'd', 's'):
+                codec_type = CODEC_TYPE_VIDEO;
+                get_le32(pb); /* codec tag */
+                get_le32(pb); /* flags */
+                get_le16(pb); /* priority */
+                get_le16(pb); /* language */
+                get_le32(pb); /* XXX: initial frame ? */
+                get_le32(pb); /* scale */
+                get_le32(pb); /* rate */
+                url_fskip(pb, size - 7 * 4);
+                break;
+            case MKTAG('a', 'u', 'd', 's'):
+                codec_type = CODEC_TYPE_AUDIO;
+                /* nothing really useful */
+                url_fskip(pb, size - 4);
+                break;
+            default:
+                goto fail;
+            }
+            break;
+        case MKTAG('s', 't', 'r', 'f'):
+            /* stream header */
+            if (stream_index >= s->nb_streams) {
+                url_fskip(pb, size);
+            } else {
+                st = s->streams[stream_index];
+                switch(codec_type) {
+                case CODEC_TYPE_VIDEO:
+                    get_le32(pb); /* size */
+                    st->codec.width = get_le32(pb);
+                    st->codec.height = get_le32(pb);
+                    if (frame_period)
+                        st->codec.frame_rate = (1000000LL * FRAME_RATE_BASE) / frame_period;
+                    else
+                        st->codec.frame_rate = 25 * FRAME_RATE_BASE;
+                    get_le16(pb); /* panes */
+                    get_le16(pb); /* depth */
+                    tag1 = get_le32(pb);
+#ifdef DEBUG
+                    print_tag("video", tag1, 0);
+#endif
+                    st->codec.codec_type = CODEC_TYPE_VIDEO;
+                    st->codec.codec_tag = tag1;
+                    st->codec.codec_id = codec_get_id(codec_bmp_tags, tag1);
+                    url_fskip(pb, size - 5 * 4);
+                    break;
+                case CODEC_TYPE_AUDIO:
+                    tag1 = get_le16(pb);
+                    st->codec.codec_type = CODEC_TYPE_AUDIO;
+                    st->codec.codec_tag = tag1;
+                    st->codec.codec_id = codec_get_id(codec_wav_tags, tag1);
+#ifdef DEBUG
+                    printf("audio: 0x%x\n", tag1);
+#endif
+                    st->codec.channels = get_le16(pb);
+                    st->codec.sample_rate = get_le32(pb);
+                    st->codec.bit_rate = get_le32(pb) * 8;
+                    url_fskip(pb, size - 3 * 4);
+                    break;
+                default:
+                    url_fskip(pb, size);
+                    break;
+                }
+            }
+            break;
+        default:
+            /* skip tag */
+            size += (size & 1);
+            url_fskip(pb, size);
+            break;
+        }
+    }
+ end_of_header:
+    /* check stream number */
+    if (stream_index != s->nb_streams - 1) {
+    fail:
+        for(i=0;i<s->nb_streams;i++) {
+            if (s->streams[i])
+                free(s->streams[i]);
+        }
+        return -1;
+    }
+        
+    return 0;
+}
+
+int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    AVIContext *avi = s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    int n, d1, d2, size;
+    
+ find_next:
+    if (url_feof(pb) || url_ftell(pb) >= avi->movi_end)
+        return -1;
+    d1 = get_byte(pb);
+    if (d1 < '0' || d1 > '9')
+        goto find_next;
+    d2 = get_byte(pb);
+    if (d2 < '0' || d2 > '9')
+        goto find_next;
+    n = (d1 - '0') * 10 + (d2 - '0');
+    
+    if (n < 0 || n >= s->nb_streams)
+        goto find_next;
+    
+    d1 = get_byte(pb);
+    d2 = get_byte(pb);
+    if ((d1 != 'd' && d2 != 'c') &&
+        (d1 != 'w' && d2 != 'b'))
+        goto find_next;
+    
+    size = get_le32(pb);
+    av_new_packet(pkt, size);
+    pkt->stream_index = n;
+
+    get_buffer(pb, pkt->data, pkt->size);
+    
+    if (size & 1)
+        get_byte(pb);
+    
+    return 0;
+}
+
+int avi_read_close(AVFormatContext *s)
+{
+    AVIContext *avi = s->priv_data;
+    free(avi);
+    return 0;
+}