change extradata format for vorbis

Originally committed as revision 4235 to svn://svn.ffmpeg.org/ffmpeg/trunk

3 files changed, 74 insertions, 23 deletions

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index bb84d158a3..b9fccc4cff 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -2357,6 +2357,8 @@ extern void av_log_set_callback(void (*)(void*, int, const char*, va_list));
                     ((uint8_t*)(x))[0])
 #endif
 
+extern unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/libavcodec/oggvorbis.c b/libavcodec/oggvorbis.c
index e5dd106424..9a47aeec97 100644
--- a/libavcodec/oggvorbis.c
+++ b/libavcodec/oggvorbis.c
@@ -49,6 +49,7 @@ static int oggvorbis_encode_init(AVCodecContext *avccontext) {
     OggVorbisContext *context = avccontext->priv_data ;
     ogg_packet header, header_comm, header_code;
     uint8_t *p;
+    unsigned int offset, len;
 
     vorbis_info_init(&context->vi) ;
     if(oggvorbis_init_encoder(&context->vi, avccontext) < 0) {
@@ -64,22 +65,21 @@ static int oggvorbis_encode_init(AVCodecContext *avccontext) {
     vorbis_analysis_headerout(&context->vd, &context->vc, &header,
                                 &header_comm, &header_code);
     
-    avccontext->extradata_size= 3*2 + header.bytes + header_comm.bytes +  header_code.bytes;
-    p= avccontext->extradata= av_mallocz(avccontext->extradata_size);
-    
-    *(p++) = header.bytes>>8;
-    *(p++) = header.bytes&0xFF;
-    memcpy(p, header.packet, header.bytes);
-    p += header.bytes;
-    
-    *(p++) = header_comm.bytes>>8;
-    *(p++) = header_comm.bytes&0xFF;
-    memcpy(p, header_comm.packet, header_comm.bytes);
-    p += header_comm.bytes;
-    
-    *(p++) = header_code.bytes>>8;
-    *(p++) = header_code.bytes&0xFF;
-    memcpy(p, header_code.packet, header_code.bytes);
+    len = header.bytes + header_comm.bytes +  header_code.bytes;
+    avccontext->extradata_size= 64 + len + len/255;
+    p = avccontext->extradata= av_mallocz(avccontext->extradata_size);
+    p[0] = 2;
+    offset = 1;
+    offset += av_xiphlacing(&p[offset], header.bytes);
+    offset += av_xiphlacing(&p[offset], header_comm.bytes);
+    memcpy(&p[offset], header.packet, header.bytes);
+    offset += header.bytes;
+    memcpy(&p[offset], header_comm.packet, header_comm.bytes);
+    offset += header_comm.bytes;
+    memcpy(&p[offset], header_code.packet, header_code.bytes);
+    offset += header_code.bytes;
+    avccontext->extradata_size = offset;
+    avccontext->extradata= av_realloc(avccontext->extradata, avccontext->extradata_size);
                                 
 /*    vorbis_block_clear(&context->vb);
     vorbis_dsp_clear(&context->vd);
@@ -184,19 +184,54 @@ AVCodec oggvorbis_encoder = {
 static int oggvorbis_decode_init(AVCodecContext *avccontext) {
     OggVorbisContext *context = avccontext->priv_data ;
     uint8_t *p= avccontext->extradata;
-    int i;
+    int i, hsizes[3];
+    unsigned char *headers[3], *extradata = avccontext->extradata;
+    unsigned int offset;
 
     vorbis_info_init(&context->vi) ;
     vorbis_comment_init(&context->vc) ;
 
+    if(! avccontext->extradata_size || ! p) {
+        av_log(avccontext, AV_LOG_ERROR, "vorbis extradata absent\n");
+        return -1;
+    }
+    if(*p != 2) {
+        av_log(avccontext, AV_LOG_ERROR,
+               "vorbis initial header len is wrong: %d\n", *p);
+        return -1;
+    }
+    offset = 1;
+    p++;
+    for(i=0; i<2; i++) {
+        hsizes[i] = 0;
+        while((*p == 0xFF) && (offset < avccontext->extradata_size)) {
+            hsizes[i] += 0xFF;
+            offset++;
+            p++;
+        }
+        if(offset >= avccontext->extradata_size - 1) {
+            av_log(avccontext, AV_LOG_ERROR, "vorbis header sizes damaged\n");
+            return -1;
+        }
+        hsizes[i] += *p;
+        offset++;
+        p++;
+    }
+    hsizes[2] = avccontext->extradata_size - hsizes[0] - hsizes[1] - offset;
+#if 0
+    av_log(avccontext, AV_LOG_DEBUG,
+           "vorbis header sizes: %d, %d, %d, / extradata_len is %d \n",
+           hsizes[0], hsizes[1], hsizes[2], avccontext->extradata_size);
+#endif
+    headers[0] = extradata + offset;
+    headers[1] = extradata + offset + hsizes[0];
+    headers[2] = extradata + offset + hsizes[0] + hsizes[1];
+
     for(i=0; i<3; i++){
         context->op.b_o_s= i==0;
-        context->op.bytes= *(p++)<<8;
-        context->op.bytes+=*(p++);
-        context->op.packet= p;
-        p += context->op.bytes;
-
-	if(vorbis_synthesis_headerin(&context->vi, &context->vc, &context->op)<0){
+        context->op.bytes = hsizes[i];
+        context->op.packet = headers[i];
+        if(vorbis_synthesis_headerin(&context->vi, &context->vc, &context->op)<0){
             av_log(avccontext, AV_LOG_ERROR, "%d. vorbis header damaged\n", i+1);
             return -1;
         }
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 3eea9a962f..16d00bc33a 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -1015,3 +1015,17 @@ int avcodec_thread_init(AVCodecContext *s, int thread_count){
     return -1;
 }
 #endif
+
+unsigned int av_xiphlacing(unsigned char *s, unsigned int v)
+{
+    unsigned int n = 0;
+
+    while(v >= 0xff) {
+        *s++ = 0xff;
+        v -= 0xff;
+        n++;
+    }
+    *s = v;
+    n++;
+    return n;
+}