DXA demuxer and decoder

Originally committed as revision 8405 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 214 insertions, 0 deletions

diff --git a/libavformat/dxa.c b/libavformat/dxa.c
new file mode 100644
index 0000000000..f49d3d4acf
--- /dev/null
+++ b/libavformat/dxa.c
@@ -0,0 +1,214 @@
+/*
+ * DXA demuxer
+ * Copyright (c) 2007 Konstantin Shishkov.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "riff.h"
+
+#define DXA_EXTRA_SIZE  9
+
+typedef struct{
+    int frames;
+    int has_sound;
+    int bpc;
+    uint32_t bytes_left;
+    int64_t wavpos, vidpos;
+    int readvid;
+}DXAContext;
+
+static int dxa_probe(AVProbeData *p)
+{
+    /* check file header */
+    if (p->buf_size <= 4)
+        return 0;
+    if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
+        p->buf[2] == 'X' && p->buf[3] == 'A')
+        return AVPROBE_SCORE_MAX;
+    else
+        return 0;
+}
+
+static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    ByteIOContext *pb = &s->pb;
+    DXAContext *c = s->priv_data;
+    AVStream *st, *ast;
+    uint32_t tag;
+    int32_t fps;
+    int w, h;
+    int num, den;
+    int flags;
+
+    tag = get_le32(pb);
+    if (tag != MKTAG('D', 'E', 'X', 'A'))
+        return -1;
+    flags = get_byte(pb);
+    c->frames = get_be16(pb);
+    if(!c->frames){
+        av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
+        return -1;
+    }
+
+    fps = get_be32(pb);
+    if(fps > 0){
+        den = 1000;
+        num = fps;
+    }else if (fps < 0){
+        den = 100000;
+        num = -fps;
+    }else{
+        den = 10;
+        num = 1;
+    }
+    w = get_be16(pb);
+    h = get_be16(pb);
+    c->has_sound = 0;
+
+    st = av_new_stream(s, 0);
+    if (!st)
+        return -1;
+
+    // Parse WAV data header
+    if(get_le32(pb) == MKTAG('W', 'A', 'V', 'E')){
+        uint32_t size, fsize;
+        c->has_sound = 1;
+        size = get_be32(pb);
+        c->vidpos = url_ftell(pb) + size;
+        url_fskip(pb, 16);
+        fsize = get_le32(pb);
+
+        ast = av_new_stream(s, 0);
+        if (!ast)
+            return -1;
+        get_wav_header(pb, ast->codec, fsize);
+        // find 'data' chunk
+        while(url_ftell(pb) < c->vidpos && !url_feof(pb)){
+            tag = get_le32(pb);
+            fsize = get_le32(pb);
+            if(tag == MKTAG('d', 'a', 't', 'a')) break;
+            url_fskip(pb, fsize);
+        }
+        c->bpc = (fsize + c->frames - 1) / c->frames;
+        if(ast->codec->block_align)
+            c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
+        c->bytes_left = fsize;
+        c->wavpos = url_ftell(pb);
+        url_fseek(pb, c->vidpos, SEEK_SET);
+    }
+
+    /* now we are ready: build format streams */
+    st->codec->codec_type = CODEC_TYPE_VIDEO;
+    st->codec->codec_id   = CODEC_ID_DXA;
+    st->codec->width      = w;
+    st->codec->height     = h;
+    av_reduce(&den, &num, den, num, (1UL<<31)-1);
+    av_set_pts_info(st, 33, num, den);
+    /* flags & 0x80 means that image is interlaced,
+     * flags & 0x40 means that image has double height
+     * either way set true height
+     */
+    if(flags & 0xC0){
+        st->codec->height >>= 1;
+    }
+    c->readvid = !c->has_sound;
+    c->vidpos  = url_ftell(pb);
+    s->start_time = 0;
+    s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
+    av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
+
+    return 0;
+}
+
+static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    DXAContext *c = s->priv_data;
+    int ret;
+    uint32_t size;
+    uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
+    int pal_size = 0;
+
+    if(!c->readvid && c->has_sound && c->bytes_left){
+        c->readvid = 1;
+        url_fseek(&s->pb, c->wavpos, SEEK_SET);
+        size = FFMIN(c->bytes_left, c->bpc);
+        ret = av_get_packet(&s->pb, pkt, size);
+        pkt->stream_index = 1;
+        if(ret != size)
+            return AVERROR_IO;
+        c->bytes_left -= size;
+        c->wavpos = url_ftell(&s->pb);
+        return 0;
+    }
+    url_fseek(&s->pb, c->vidpos, SEEK_SET);
+    while(!url_feof(&s->pb) && c->frames){
+        get_buffer(&s->pb, buf, 4);
+        switch(AV_RL32(buf)){
+        case MKTAG('N', 'U', 'L', 'L'):
+            if(av_new_packet(pkt, 4 + pal_size) < 0)
+                return AVERROR_NOMEM;
+            pkt->stream_index = 0;
+            if(pal_size) memcpy(pkt->data, pal, pal_size);
+            memcpy(pkt->data + pal_size, buf, 4);
+            c->frames--;
+            c->vidpos = url_ftell(&s->pb);
+            c->readvid = 0;
+            return 0;
+        case MKTAG('C', 'M', 'A', 'P'):
+            pal_size = 768+4;
+            memcpy(pal, buf, 4);
+            get_buffer(&s->pb, pal + 4, 768);
+            break;
+        case MKTAG('F', 'R', 'A', 'M'):
+            get_buffer(&s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
+            size = AV_RB32(buf + 5);
+            if(size > 0xFFFFFF){
+                av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
+                return -1;
+            }
+            if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
+                return AVERROR_NOMEM;
+            memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
+            ret = get_buffer(&s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
+            if(ret != size){
+                av_free_packet(pkt);
+                return AVERROR_IO;
+            }
+            if(pal_size) memcpy(pkt->data, pal, pal_size);
+            pkt->stream_index = 0;
+            c->frames--;
+            c->vidpos = url_ftell(&s->pb);
+            c->readvid = 0;
+            return 0;
+        default:
+            av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
+            return -1;
+        }
+    }
+    return AVERROR(EIO);
+}
+
+AVInputFormat dxa_demuxer = {
+    "dxa",
+    "dxa",
+    sizeof(DXAContext),
+    dxa_probe,
+    dxa_read_header,
+    dxa_read_packet,
+};