diff --git a/libavformat/aea.c b/libavformat/aea.c
index 25450a4841..e360b10415 100644
--- a/libavformat/aea.c
+++ b/libavformat/aea.c
@@ -99,7 +99,7 @@ AVInputFormat ff_aea_demuxer = {
     .read_probe     = aea_read_probe,
     .read_header    = aea_read_header,
     .read_packet    = aea_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
     .flags= AVFMT_GENERIC_INDEX,
     .extensions = "aea",
 };
diff --git a/libavformat/aiffdec.c b/libavformat/aiffdec.c
index 46396cda6f..c6b51877b5 100644
--- a/libavformat/aiffdec.c
+++ b/libavformat/aiffdec.c
@@ -318,6 +318,6 @@ AVInputFormat ff_aiff_demuxer = {
     .read_probe     = aiff_probe,
     .read_header    = aiff_read_header,
     .read_packet    = aiff_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
     .codec_tag= (const AVCodecTag* const []){ff_codec_aiff_tags, 0},
 };
diff --git a/libavformat/au.c b/libavformat/au.c
index e56869b4b9..dddc854ade 100644
--- a/libavformat/au.c
+++ b/libavformat/au.c
@@ -190,7 +190,7 @@ AVInputFormat ff_au_demuxer = {
     .read_probe     = au_probe,
     .read_header    = au_read_header,
     .read_packet    = au_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
     .codec_tag= (const AVCodecTag* const []){codec_au_tags, 0},
 };
 #endif
diff --git a/libavformat/avidec.c b/libavformat/avidec.c
index 26ccaadd12..82db45abf3 100644
--- a/libavformat/avidec.c
+++ b/libavformat/avidec.c
@@ -1306,7 +1306,7 @@ static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp
 
         /* Feed the DV video stream version of the timestamp to the */
         /* DV demux so it can synthesize correct timestamps.        */
-        dv_offset_reset(avi->dv_demux, timestamp);
+        ff_dv_offset_reset(avi->dv_demux, timestamp);
 
         avio_seek(s->pb, pos, SEEK_SET);
         avi->stream_index= -1;
diff --git a/libavformat/avs.c b/libavformat/avs.c
index 32e7546d60..22b4614cb8 100644
--- a/libavformat/avs.c
+++ b/libavformat/avs.c
@@ -124,7 +124,7 @@ static int avs_read_audio_packet(AVFormatContext * s, AVPacket * pkt)
     int ret, size;
 
     size = avio_tell(s->pb);
-    ret = voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
+    ret = ff_voc_get_packet(s, pkt, avs->st_audio, avs->remaining_audio_size);
     size = avio_tell(s->pb) - size;
     avs->remaining_audio_size -= size;
 
diff --git a/libavformat/c93.c b/libavformat/c93.c
index 21058da727..f8f8f96ddc 100644
--- a/libavformat/c93.c
+++ b/libavformat/c93.c
@@ -123,7 +123,7 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt)
                 c93->audio->codec->codec_type = AVMEDIA_TYPE_AUDIO;
             }
             avio_skip(pb, 26); /* VOC header */
-            ret = voc_get_packet(s, pkt, c93->audio, datasize - 26);
+            ret = ff_voc_get_packet(s, pkt, c93->audio, datasize - 26);
             if (ret > 0) {
                 pkt->stream_index = 1;
                 pkt->flags |= AV_PKT_FLAG_KEY;
diff --git a/libavformat/cutils.c b/libavformat/cutils.c
index 995524400e..f58e152cac 100644
--- a/libavformat/cutils.c
+++ b/libavformat/cutils.c
@@ -47,7 +47,7 @@ void ff_dynarray_add(intptr_t **tab_ptr, int *nb_ptr, intptr_t elem)
 
 /* This is our own gmtime_r. It differs from its POSIX counterpart in a
    couple of places, though. */
-struct tm *brktimegm(time_t secs, struct tm *tm)
+struct tm *ff_brktimegm(time_t secs, struct tm *tm)
 {
     int days, y, ny, m;
     int md[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
diff --git a/libavformat/dv.c b/libavformat/dv.c
index 6714bf2afc..873cc3fe3d 100644
--- a/libavformat/dv.c
+++ b/libavformat/dv.c
@@ -402,7 +402,7 @@ static int64_t dv_frame_offset(AVFormatContext *s, DVDemuxContext *c,
     return offset + s->data_offset;
 }
 
-void dv_offset_reset(DVDemuxContext *c, int64_t frame_offset)
+void ff_dv_offset_reset(DVDemuxContext *c, int64_t frame_offset)
 {
     c->frames= frame_offset;
     if (c->ach)
@@ -494,7 +494,7 @@ static int dv_read_seek(AVFormatContext *s, int stream_index,
     if (avio_seek(s->pb, offset, SEEK_SET) < 0)
         return -1;
 
-    dv_offset_reset(c, offset / c->sys->frame_size);
+    ff_dv_offset_reset(c, offset / c->sys->frame_size);
     return 0;
 }
 
diff --git a/libavformat/dv.h b/libavformat/dv.h
index b4bb10d4bc..e8b2d37904 100644
--- a/libavformat/dv.h
+++ b/libavformat/dv.h
@@ -34,7 +34,7 @@ typedef struct DVDemuxContext DVDemuxContext;
 DVDemuxContext* avpriv_dv_init_demux(AVFormatContext* s);
 int avpriv_dv_get_packet(DVDemuxContext*, AVPacket *);
 int avpriv_dv_produce_packet(DVDemuxContext*, AVPacket*, uint8_t*, int);
-void dv_offset_reset(DVDemuxContext *c, int64_t frame_offset);
+void ff_dv_offset_reset(DVDemuxContext *c, int64_t frame_offset);
 
 typedef struct DVMuxContext DVMuxContext;
 
diff --git a/libavformat/dvenc.c b/libavformat/dvenc.c
index 56db4d2691..8ebdd7fa1d 100644
--- a/libavformat/dvenc.c
+++ b/libavformat/dvenc.c
@@ -82,7 +82,7 @@ static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* bu
     case dv_timecode:
         ct = (time_t)av_rescale_rnd(c->frames, c->sys->time_base.num,
                                     c->sys->time_base.den, AV_ROUND_DOWN);
-        brktimegm(ct, &tc);
+        ff_brktimegm(ct, &tc);
         /*
          * LTC drop-frame frame counter drops two frames (0 and 1) every
          * minute, unless it is exactly divisible by 10
@@ -143,7 +143,7 @@ static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* bu
     case dv_video_recdate:  /* VAUX recording date */
         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
                                             c->sys->time_base.den, AV_ROUND_DOWN);
-        brktimegm(ct, &tc);
+        ff_brktimegm(ct, &tc);
         buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
                        /* 0xff is very likely to be "unknown" */
         buf[2] = (3 << 6) | /* reserved -- always 1 */
@@ -159,7 +159,7 @@ static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* bu
     case dv_video_rectime:  /* VAUX recording time */
         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
                                                        c->sys->time_base.den, AV_ROUND_DOWN);
-        brktimegm(ct, &tc);
+        ff_brktimegm(ct, &tc);
         buf[1] = (3 << 6) | /* reserved -- always 1 */
                  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
         buf[2] = (1 << 7) | /* reserved -- always 1 */
diff --git a/libavformat/internal.h b/libavformat/internal.h
index 322dff94af..fb298539b6 100644
--- a/libavformat/internal.h
+++ b/libavformat/internal.h
@@ -54,7 +54,7 @@ do {\
 } while(0)
 #endif
 
-struct tm *brktimegm(time_t secs, struct tm *tm);
+struct tm *ff_brktimegm(time_t secs, struct tm *tm);
 
 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
 
diff --git a/libavformat/isom.c b/libavformat/isom.c
index eab304c006..51e89a0a62 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -66,7 +66,7 @@ const AVCodecTag ff_mp4_obj_type[] = {
     { CODEC_ID_NONE      ,    0 },
 };
 
-const AVCodecTag codec_movvideo_tags[] = {
+const AVCodecTag ff_codec_movvideo_tags[] = {
 /*  { CODEC_ID_, MKTAG('I', 'V', '5', '0') }, *//* Indeo 5.0 */
 
     { CODEC_ID_RAWVIDEO, MKTAG('r', 'a', 'w', ' ') }, /* Uncompressed RGB */
@@ -223,7 +223,7 @@ const AVCodecTag codec_movvideo_tags[] = {
     { CODEC_ID_NONE, 0 },
 };
 
-const AVCodecTag codec_movaudio_tags[] = {
+const AVCodecTag ff_codec_movaudio_tags[] = {
     { CODEC_ID_AAC,             MKTAG('m', 'p', '4', 'a') },
     { CODEC_ID_AC3,             MKTAG('a', 'c', '-', '3') }, /* ETSI TS 102 366 Annex F */
     { CODEC_ID_AC3,             MKTAG('s', 'a', 'c', '3') }, /* Nero Recode */
diff --git a/libavformat/isom.h b/libavformat/isom.h
index 91fbf759f8..e74a552644 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -30,8 +30,8 @@
 
 /* isom.c */
 extern const AVCodecTag ff_mp4_obj_type[];
-extern const AVCodecTag codec_movvideo_tags[];
-extern const AVCodecTag codec_movaudio_tags[];
+extern const AVCodecTag ff_codec_movvideo_tags[];
+extern const AVCodecTag ff_codec_movaudio_tags[];
 extern const AVCodecTag ff_codec_movsubtitle_tags[];
 
 int ff_mov_iso639_to_lang(const char lang[4], int mp4);
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index ca211a2786..31b40a8386 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -1422,7 +1422,7 @@ static int matroska_read_header(AVFormatContext *s)
                    && (track->codec_priv.size >= 86)
                    && (track->codec_priv.data != NULL)) {
             track->video.fourcc = AV_RL32(track->codec_priv.data);
-            codec_id=ff_codec_get_id(codec_movvideo_tags, track->video.fourcc);
+            codec_id=ff_codec_get_id(ff_codec_movvideo_tags, track->video.fourcc);
         } else if (codec_id == CODEC_ID_PCM_S16BE) {
             switch (track->audio.bitdepth) {
             case  8:  codec_id = CODEC_ID_PCM_U8;     break;
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index e93dd65dff..984d0f1565 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -480,7 +480,7 @@ static int mkv_write_codecprivate(AVFormatContext *s, AVIOContext *pb, AVCodecCo
     } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
         if (qt_id) {
             if (!codec->codec_tag)
-                codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id);
+                codec->codec_tag = ff_codec_get_tag(ff_codec_movvideo_tags, codec->codec_id);
             if (codec->extradata_size)
                 avio_write(dyn_cp, codec->extradata, codec->extradata_size);
         } else {
@@ -583,7 +583,7 @@ static int mkv_write_tracks(AVFormatContext *s)
                 put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, av_q2d(codec->time_base)*1E9);
 
                 if (!native_id &&
-                      ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
+                      ff_codec_get_tag(ff_codec_movvideo_tags, codec->codec_id) &&
                     (!ff_codec_get_tag(ff_codec_bmp_tags,   codec->codec_id)
                      || codec->codec_id == CODEC_ID_SVQ1
                      || codec->codec_id == CODEC_ID_SVQ3
diff --git a/libavformat/mmf.c b/libavformat/mmf.c
index 4d34cf2ac4..837b5cd67a 100644
--- a/libavformat/mmf.c
+++ b/libavformat/mmf.c
@@ -297,7 +297,7 @@ AVInputFormat ff_mmf_demuxer = {
     .read_probe     = mmf_probe,
     .read_header    = mmf_read_header,
     .read_packet    = mmf_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
 };
 #endif
 #if CONFIG_MMF_MUXER
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 9deb820ebd..690cd1ed46 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -1126,7 +1126,7 @@ int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
 
         if (st->codec->codec_tag &&
             st->codec->codec_tag != format &&
-            (c->fc->video_codec_id ? ff_codec_get_id(codec_movvideo_tags, format) != c->fc->video_codec_id
+            (c->fc->video_codec_id ? ff_codec_get_id(ff_codec_movvideo_tags, format) != c->fc->video_codec_id
                                    : st->codec->codec_tag != MKTAG('j','p','e','g'))
            ){
             /* Multiple fourcc, we skip JPEG. This is not correct, we should
@@ -1144,7 +1144,7 @@ int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
         sc->dref_id= dref_id;
 
         st->codec->codec_tag = format;
-        id = ff_codec_get_id(codec_movaudio_tags, format);
+        id = ff_codec_get_id(ff_codec_movaudio_tags, format);
         if (id<=0 && ((format&0xFFFF) == 'm'+('s'<<8) || (format&0xFFFF) == 'T'+('S'<<8)))
             id = ff_codec_get_id(ff_codec_wav_tags, av_bswap32(format)&0xFFFF);
 
@@ -1152,7 +1152,7 @@ int ff_mov_read_stsd_entries(MOVContext *c, AVIOContext *pb, int entries)
             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
         } else if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO && /* do not overwrite codec type */
                    format && format != MKTAG('m','p','4','s')) { /* skip old asf mpeg4 tag */
-            id = ff_codec_get_id(codec_movvideo_tags, format);
+            id = ff_codec_get_id(ff_codec_movvideo_tags, format);
             if (id <= 0)
                 id = ff_codec_get_id(ff_codec_bmp_tags, format);
             if (id > 0)
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 4193ec5e64..ce00866df8 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -829,7 +829,7 @@ static int mov_get_codec_tag(AVFormatContext *s, MOVTrack *track)
         else if (track->enc->codec_id == CODEC_ID_RAWVIDEO)
             tag = mov_get_rawvideo_codec_tag(s, track);
         else if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO) {
-            tag = ff_codec_get_tag(codec_movvideo_tags, track->enc->codec_id);
+            tag = ff_codec_get_tag(ff_codec_movvideo_tags, track->enc->codec_id);
             if (!tag) { // if no mac fcc found, try with Microsoft tags
                 tag = ff_codec_get_tag(ff_codec_bmp_tags, track->enc->codec_id);
                 if (tag)
@@ -837,7 +837,7 @@ static int mov_get_codec_tag(AVFormatContext *s, MOVTrack *track)
                            "the file may be unplayable!\n");
             }
         } else if (track->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
-            tag = ff_codec_get_tag(codec_movaudio_tags, track->enc->codec_id);
+            tag = ff_codec_get_tag(ff_codec_movaudio_tags, track->enc->codec_id);
             if (!tag) { // if no mac fcc found, try with Microsoft tags
                 int ms_tag = ff_codec_get_tag(ff_codec_wav_tags, track->enc->codec_id);
                 if (ms_tag) {
@@ -3230,7 +3230,7 @@ AVOutputFormat ff_mov_muxer = {
     .write_packet      = ff_mov_write_packet,
     .write_trailer     = mov_write_trailer,
     .flags = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH,
-    .codec_tag = (const AVCodecTag* const []){codec_movvideo_tags, codec_movaudio_tags, 0},
+    .codec_tag = (const AVCodecTag* const []){ff_codec_movvideo_tags, ff_codec_movaudio_tags, 0},
     .priv_class = &mov_muxer_class,
 };
 #endif
diff --git a/libavformat/omadec.c b/libavformat/omadec.c
index 60b42fa9a9..fc9c2921e6 100644
--- a/libavformat/omadec.c
+++ b/libavformat/omadec.c
@@ -412,7 +412,7 @@ static int oma_read_seek(struct AVFormatContext *s, int stream_index, int64_t ti
 {
     OMAContext *oc = s->priv_data;
 
-    pcm_read_seek(s, stream_index, timestamp, flags);
+    ff_pcm_read_seek(s, stream_index, timestamp, flags);
 
     if (oc->encrypted) {
         /* readjust IV for CBC */
diff --git a/libavformat/pcm.c b/libavformat/pcm.c
index 7d5fed5601..892e8ca24e 100644
--- a/libavformat/pcm.c
+++ b/libavformat/pcm.c
@@ -23,8 +23,8 @@
 #include "avformat.h"
 #include "pcm.h"
 
-int pcm_read_seek(AVFormatContext *s,
-                  int stream_index, int64_t timestamp, int flags)
+int ff_pcm_read_seek(AVFormatContext *s,
+                     int stream_index, int64_t timestamp, int flags)
 {
     AVStream *st;
     int block_align, byte_rate;
diff --git a/libavformat/pcm.h b/libavformat/pcm.h
index 228df1394b..30cbc86ee3 100644
--- a/libavformat/pcm.h
+++ b/libavformat/pcm.h
@@ -24,7 +24,7 @@
 
 #include "avformat.h"
 
-int pcm_read_seek(AVFormatContext *s,
-                  int stream_index, int64_t timestamp, int flags);
+int ff_pcm_read_seek(AVFormatContext *s,
+                     int stream_index, int64_t timestamp, int flags);
 
 #endif /* AVFORMAT_PCM_H */
diff --git a/libavformat/pcmdec.c b/libavformat/pcmdec.c
index 1e36cc4e76..512bc0a21e 100644
--- a/libavformat/pcmdec.c
+++ b/libavformat/pcmdec.c
@@ -67,7 +67,7 @@ AVInputFormat ff_pcm_ ## name_ ## _demuxer = {              \
     .priv_data_size = sizeof(RawAudioDemuxerContext),       \
     .read_header    = ff_raw_read_header,                   \
     .read_packet    = raw_read_packet,                      \
-    .read_seek      = pcm_read_seek,                        \
+    .read_seek      = ff_pcm_read_seek,                     \
     .flags          = AVFMT_GENERIC_INDEX,                  \
     .extensions     = ext,                                  \
     .raw_codec_id   = codec,                                \
diff --git a/libavformat/rsodec.c b/libavformat/rsodec.c
index c148b2ee57..72c12e7421 100644
--- a/libavformat/rsodec.c
+++ b/libavformat/rsodec.c
@@ -94,6 +94,6 @@ AVInputFormat ff_rso_demuxer = {
     .extensions     =   "rso",
     .read_header    =   rso_read_header,
     .read_packet    =   rso_read_packet,
-    .read_seek      =   pcm_read_seek,
+    .read_seek      =   ff_pcm_read_seek,
     .codec_tag      =   (const AVCodecTag* const []){ff_codec_rso_tags, 0},
 };
diff --git a/libavformat/sol.c b/libavformat/sol.c
index 4b3a5adbc0..d02373c65a 100644
--- a/libavformat/sol.c
+++ b/libavformat/sol.c
@@ -147,5 +147,5 @@ AVInputFormat ff_sol_demuxer = {
     .read_probe     = sol_probe,
     .read_header    = sol_read_header,
     .read_packet    = sol_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
 };
diff --git a/libavformat/soxdec.c b/libavformat/soxdec.c
index 29d13d4f7b..6ce1848539 100644
--- a/libavformat/soxdec.c
+++ b/libavformat/soxdec.c
@@ -148,5 +148,5 @@ AVInputFormat ff_sox_demuxer = {
     .read_probe     = sox_probe,
     .read_header    = sox_read_header,
     .read_packet    = sox_read_packet,
-    .read_seek      = pcm_read_seek,
+    .read_seek      = ff_pcm_read_seek,
 };
diff --git a/libavformat/voc.h b/libavformat/voc.h
index abd8fdbfff..1668618fda 100644
--- a/libavformat/voc.h
+++ b/libavformat/voc.h
@@ -45,7 +45,7 @@ typedef enum voc_type {
 extern const unsigned char ff_voc_magic[21];
 extern const AVCodecTag ff_voc_codec_tags[];
 
-int voc_get_packet(AVFormatContext *s, AVPacket *pkt,
-                   AVStream *st, int max_size);
+int ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt,
+                      AVStream *st, int max_size);
 
 #endif /* AVFORMAT_VOC_H */
diff --git a/libavformat/vocdec.c b/libavformat/vocdec.c
index 6b3438f758..e8c11afbe3 100644
--- a/libavformat/vocdec.c
+++ b/libavformat/vocdec.c
@@ -62,7 +62,7 @@ static int voc_read_header(AVFormatContext *s)
 }
 
 int
-voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
+ff_voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
 {
     VocDecContext *voc = s->priv_data;
     AVCodecContext *dec = st->codec;
@@ -153,7 +153,7 @@ voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
 
 static int voc_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
-    return voc_get_packet(s, pkt, s->streams[0], 0);
+    return ff_voc_get_packet(s, pkt, s->streams[0], 0);
 }
 
 AVInputFormat ff_voc_demuxer = {
diff --git a/libavformat/wav.c b/libavformat/wav.c
index 7b3a0f44f3..bccc3dbdee 100644
--- a/libavformat/wav.c
+++ b/libavformat/wav.c
@@ -582,7 +582,7 @@ static int wav_read_seek(AVFormatContext *s,
     default:
         break;
     }
-    return pcm_read_seek(s, stream_index, timestamp, flags);
+    return ff_pcm_read_seek(s, stream_index, timestamp, flags);
 }
 
 AVInputFormat ff_wav_demuxer = {