diff --git a/libavformat/asf.h b/libavformat/asf.h
index 0867755f46..f3705e946a 100644
--- a/libavformat/asf.h
+++ b/libavformat/asf.h
@@ -231,5 +231,7 @@ extern const AVMetadataConv ff_asf_metadata_conv[];
 
 extern AVInputFormat asf_demuxer;
 int ff_put_str16_nolen(ByteIOContext *s, const char *tag);
+int ff_guidcmp(const void *g1, const void *g2);
+void ff_get_guid(ByteIOContext *s, ff_asf_guid *g);
 
 #endif /* AVFORMAT_ASF_H */
diff --git a/libavformat/asfdec.c b/libavformat/asfdec.c
index 36876fa1fd..6ae4e99326 100644
--- a/libavformat/asfdec.c
+++ b/libavformat/asfdec.c
@@ -49,14 +49,14 @@ static const ff_asf_guid stream_bitrate_guid = { /* (http://get.to/sdp) */
 /**********************************/
 /* decoding */
 
-static int guidcmp(const void *g1, const void *g2)
+int ff_guidcmp(const void *g1, const void *g2)
 {
     return memcmp(g1, g2, sizeof(ff_asf_guid));
 }
 
 #ifdef DEBUG
 #define PRINT_IF_GUID(g,cmp) \
-if (!guidcmp(g, &cmp)) \
+if (!ff_guidcmp(g, &cmp)) \
     dprintf(NULL, "(GUID: %s) ", #cmp)
 
 static void print_guid(const ff_asf_guid *g)
@@ -97,7 +97,7 @@ static void print_guid(const ff_asf_guid *g)
 #define print_guid(g)
 #endif
 
-static void get_guid(ByteIOContext *s, ff_asf_guid *g)
+void ff_get_guid(ByteIOContext *s, ff_asf_guid *g)
 {
     assert(sizeof(*g) == 16);
     get_buffer(s, *g, sizeof(*g));
@@ -139,7 +139,7 @@ static void get_str16_nolen(ByteIOContext *pb, int len, char *buf, int buf_size)
 static int asf_probe(AVProbeData *pd)
 {
     /* check file header */
-    if (!guidcmp(pd->buf, &ff_asf_header))
+    if (!ff_guidcmp(pd->buf, &ff_asf_header))
         return AVPROBE_SCORE_MAX;
     else
         return 0;
@@ -196,8 +196,8 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
     memset(dar, 0, sizeof(dar));
     memset(bitrate, 0, sizeof(bitrate));
 
-    get_guid(pb, &g);
-    if (guidcmp(&g, &ff_asf_header))
+    ff_get_guid(pb, &g);
+    if (ff_guidcmp(&g, &ff_asf_header))
         return -1;
     get_le64(pb);
     get_le32(pb);
@@ -206,12 +206,12 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
     memset(&asf->asfid2avid, -1, sizeof(asf->asfid2avid));
     for(;;) {
         uint64_t gpos= url_ftell(pb);
-        get_guid(pb, &g);
+        ff_get_guid(pb, &g);
         gsize = get_le64(pb);
         dprintf(s, "%08"PRIx64": ", gpos);
         print_guid(&g);
         dprintf(s, "  size=0x%"PRIx64"\n", gsize);
-        if (!guidcmp(&g, &ff_asf_data_header)) {
+        if (!ff_guidcmp(&g, &ff_asf_data_header)) {
             asf->data_object_offset = url_ftell(pb);
             // if not streaming, gsize is not unlimited (how?), and there is enough space in the file..
             if (!(asf->hdr.flags & 0x01) && gsize >= 100) {
@@ -223,8 +223,8 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
         }
         if (gsize < 24)
             return -1;
-        if (!guidcmp(&g, &ff_asf_file_header)) {
-            get_guid(pb, &asf->hdr.guid);
+        if (!ff_guidcmp(&g, &ff_asf_file_header)) {
+            ff_get_guid(pb, &asf->hdr.guid);
             asf->hdr.file_size          = get_le64(pb);
             asf->hdr.create_time        = get_le64(pb);
             asf->nb_packets             = get_le64(pb);
@@ -237,7 +237,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             asf->hdr.max_pktsize        = get_le32(pb);
             asf->hdr.max_bitrate        = get_le32(pb);
             s->packet_size = asf->hdr.max_pktsize;
-        } else if (!guidcmp(&g, &ff_asf_stream_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_stream_header)) {
             enum AVMediaType type;
             int type_specific_size, sizeX;
             uint64_t total_size;
@@ -268,25 +268,25 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                 st->duration = asf->hdr.play_time /
                     (10000000 / 1000) - start_time;
             }
-            get_guid(pb, &g);
+            ff_get_guid(pb, &g);
 
             test_for_ext_stream_audio = 0;
-            if (!guidcmp(&g, &ff_asf_audio_stream)) {
+            if (!ff_guidcmp(&g, &ff_asf_audio_stream)) {
                 type = AVMEDIA_TYPE_AUDIO;
-            } else if (!guidcmp(&g, &ff_asf_video_stream)) {
+            } else if (!ff_guidcmp(&g, &ff_asf_video_stream)) {
                 type = AVMEDIA_TYPE_VIDEO;
-            } else if (!guidcmp(&g, &ff_asf_jfif_media)) {
+            } else if (!ff_guidcmp(&g, &ff_asf_jfif_media)) {
                 type = AVMEDIA_TYPE_VIDEO;
                 st->codec->codec_id = CODEC_ID_MJPEG;
-            } else if (!guidcmp(&g, &ff_asf_command_stream)) {
+            } else if (!ff_guidcmp(&g, &ff_asf_command_stream)) {
                 type = AVMEDIA_TYPE_DATA;
-            } else if (!guidcmp(&g, &ff_asf_ext_stream_embed_stream_header)) {
+            } else if (!ff_guidcmp(&g, &ff_asf_ext_stream_embed_stream_header)) {
                 test_for_ext_stream_audio = 1;
                 type = AVMEDIA_TYPE_UNKNOWN;
             } else {
                 return -1;
             }
-            get_guid(pb, &g);
+            ff_get_guid(pb, &g);
             total_size = get_le64(pb);
             type_specific_size = get_le32(pb);
             get_le32(pb);
@@ -297,15 +297,15 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             get_le32(pb);
 
             if (test_for_ext_stream_audio) {
-                get_guid(pb, &g);
-                if (!guidcmp(&g, &ff_asf_ext_stream_audio_stream)) {
+                ff_get_guid(pb, &g);
+                if (!ff_guidcmp(&g, &ff_asf_ext_stream_audio_stream)) {
                     type = AVMEDIA_TYPE_AUDIO;
                     is_dvr_ms_audio=1;
-                    get_guid(pb, &g);
+                    ff_get_guid(pb, &g);
                     get_le32(pb);
                     get_le32(pb);
                     get_le32(pb);
-                    get_guid(pb, &g);
+                    ff_get_guid(pb, &g);
                     get_le32(pb);
                 }
             }
@@ -413,7 +413,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             }
             pos2 = url_ftell(pb);
             url_fskip(pb, gsize - (pos2 - pos1 + 24));
-        } else if (!guidcmp(&g, &ff_asf_comment_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_comment_header)) {
             int len1, len2, len3, len4, len5;
 
             len1 = get_le16(pb);
@@ -426,7 +426,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             get_tag(s, "copyright", 0, len3);
             get_tag(s, "comment"  , 0, len4);
             url_fskip(pb, len5);
-        } else if (!guidcmp(&g, &stream_bitrate_guid)) {
+        } else if (!ff_guidcmp(&g, &stream_bitrate_guid)) {
             int stream_count = get_le16(pb);
             int j;
 
@@ -441,7 +441,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
 //                av_log(s, AV_LOG_ERROR, "flags: 0x%x stream id %d, bitrate %d\n", flags, stream_id, bitrate);
                 asf->stream_bitrates[stream_id]= bitrate;
             }
-        } else if (!guidcmp(&g, &ff_asf_language_guid)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_language_guid)) {
             int j;
             int stream_count = get_le16(pb);
             for(j = 0; j < stream_count; j++) {
@@ -451,7 +451,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                 if (j < 128)
                     av_strlcpy(asf->stream_languages[j], lang, sizeof(*asf->stream_languages));
             }
-        } else if (!guidcmp(&g, &ff_asf_extended_content_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_extended_content_header)) {
             int desc_count, i;
 
             desc_count = get_le16(pb);
@@ -478,7 +478,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                     } else
                         get_tag(s, name, value_type, value_len);
             }
-        } else if (!guidcmp(&g, &ff_asf_metadata_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_metadata_header)) {
             int n, stream_num, name_len, value_len, value_type, value_num;
             n = get_le16(pb);
 
@@ -501,7 +501,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                     else if(!strcmp(name, "AspectRatioY")) dar[stream_num].den= value_num;
                 }
             }
-        } else if (!guidcmp(&g, &ff_asf_ext_stream_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_ext_stream_header)) {
             int ext_len, payload_ext_ct, stream_ct;
             uint32_t ext_d, leak_rate, stream_num;
             unsigned int stream_languageid_index;
@@ -536,7 +536,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             }
 
             for (i=0; i<payload_ext_ct; i++){
-                get_guid(pb, &g);
+                ff_get_guid(pb, &g);
                 ext_d=get_le16(pb);
                 ext_len=get_le32(pb);
                 url_fseek(pb, ext_len, SEEK_CUR);
@@ -545,13 +545,13 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             // there could be a optional stream properties object to follow
             // if so the next iteration will pick it up
             continue;
-        } else if (!guidcmp(&g, &ff_asf_head1_guid)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_head1_guid)) {
             int v1, v2;
-            get_guid(pb, &g);
+            ff_get_guid(pb, &g);
             v1 = get_le32(pb);
             v2 = get_le16(pb);
             continue;
-        } else if (!guidcmp(&g, &ff_asf_marker_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_marker_header)) {
             int i, count, name_len;
             char name[1024];
 
@@ -578,12 +578,12 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                 ff_new_chapter(s, i, (AVRational){1, 10000000}, pres_time, AV_NOPTS_VALUE, name );
             }
 #if 0
-        } else if (!guidcmp(&g, &ff_asf_codec_comment_header)) {
+        } else if (!ff_guidcmp(&g, &ff_asf_codec_comment_header)) {
             int len, v1, n, num;
             char str[256], *q;
             char tag[16];
 
-            get_guid(pb, &g);
+            ff_get_guid(pb, &g);
             print_guid(&g);
 
             n = get_le32(pb);
@@ -606,11 +606,11 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             return -1;
         } else {
             if (!s->keylen) {
-                if (!guidcmp(&g, &ff_asf_content_encryption)) {
+                if (!ff_guidcmp(&g, &ff_asf_content_encryption)) {
                     av_log(s, AV_LOG_WARNING, "DRM protected stream detected, decoding will likely fail!\n");
-                } else if (!guidcmp(&g, &ff_asf_ext_content_encryption)) {
+                } else if (!ff_guidcmp(&g, &ff_asf_ext_content_encryption)) {
                     av_log(s, AV_LOG_WARNING, "Ext DRM protected stream detected, decoding will likely fail!\n");
-                } else if (!guidcmp(&g, &ff_asf_digital_signature)) {
+                } else if (!ff_guidcmp(&g, &ff_asf_digital_signature)) {
                     av_log(s, AV_LOG_WARNING, "Digital signature detected, decoding will likely fail!\n");
                 }
             }
@@ -619,7 +619,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
             av_log(s, AV_LOG_DEBUG, "gpos mismatch our pos=%"PRIu64", end=%"PRIu64"\n", url_ftell(pb)-gpos, gsize);
         url_fseek(pb, gpos + gsize, SEEK_SET);
     }
-    get_guid(pb, &g);
+    ff_get_guid(pb, &g);
     get_le64(pb);
     get_byte(pb);
     get_byte(pb);
@@ -1153,25 +1153,25 @@ static void asf_build_simple_index(AVFormatContext *s, int stream_index)
     int i;
 
     url_fseek(s->pb, asf->data_object_offset + asf->data_object_size, SEEK_SET);
-    get_guid(s->pb, &g);
+    ff_get_guid(s->pb, &g);
 
     /* the data object can be followed by other top-level objects,
        skip them until the simple index object is reached */
-    while (guidcmp(&g, &index_guid)) {
+    while (ff_guidcmp(&g, &index_guid)) {
         int64_t gsize= get_le64(s->pb);
         if (gsize < 24 || url_feof(s->pb)) {
             url_fseek(s->pb, current_pos, SEEK_SET);
             return;
         }
         url_fseek(s->pb, gsize-24, SEEK_CUR);
-        get_guid(s->pb, &g);
+        ff_get_guid(s->pb, &g);
     }
 
     {
         int64_t itime, last_pos=-1;
         int pct, ict;
         int64_t av_unused gsize= get_le64(s->pb);
-        get_guid(s->pb, &g);
+        ff_get_guid(s->pb, &g);
         itime=get_le64(s->pb);
         pct=get_le32(s->pb);
         ict=get_le32(s->pb);