diff --git a/libavfilter/audio.h b/libavfilter/audio.h
index 3335c96eca..6adc82dc81 100644
--- a/libavfilter/audio.h
+++ b/libavfilter/audio.h
@@ -60,24 +60,4 @@ AVFrame *ff_null_get_audio_buffer(AVFilterLink *link, int nb_samples);
  */
 AVFrame *ff_get_audio_buffer(AVFilterLink *link, int nb_samples);
 
-/**
- * Send a buffer of audio samples to the next filter.
- *
- * @param link       the output link over which the audio samples are being sent
- * @param samplesref a reference to the buffer of audio samples being sent. The
- *                   receiving filter will free this reference when it no longer
- *                   needs it or pass it on to the next filter.
- *
- * @return >= 0 on success, a negative AVERROR on error. The receiving filter
- * is responsible for unreferencing samplesref in case of error.
- */
-int ff_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref);
-
-/**
- * Send a buffer of audio samples to the next link, without checking
- * min_samples.
- */
-int ff_filter_samples_framed(AVFilterLink *link,
-                             AVFilterBufferRef *samplesref);
-
 #endif /* AVFILTER_AUDIO_H */
diff --git a/libavfilter/avfilter.c b/libavfilter/avfilter.c
index bcf8d3f91f..d43d8136ba 100644
--- a/libavfilter/avfilter.c
+++ b/libavfilter/avfilter.c
@@ -1024,7 +1024,6 @@ static int ff_filter_frame_framed(AVFilterLink *link, AVFrame *frame)
     if (dst->needs_writable && !av_frame_is_writable(frame)) {
         av_log(link->dst, AV_LOG_DEBUG, "Copying data in avfilter.\n");
 
-        /* Maybe use ff_copy_buffer_ref instead? */
         switch (link->type) {
         case AVMEDIA_TYPE_VIDEO:
             out = ff_get_video_buffer(link, link->w, link->h);
diff --git a/libavfilter/internal.h b/libavfilter/internal.h
index 85348f001e..797c88437c 100644
--- a/libavfilter/internal.h
+++ b/libavfilter/internal.h
@@ -338,9 +338,6 @@ int ff_request_frame(AVFilterLink *link);
         .category   = AV_CLASS_CATEGORY_FILTER, \
     }
 
-AVFilterBufferRef *ff_copy_buffer_ref(AVFilterLink *outlink,
-                                      AVFilterBufferRef *ref);
-
 /**
  * Find the index of a link.
  *
@@ -349,9 +346,6 @@ AVFilterBufferRef *ff_copy_buffer_ref(AVFilterLink *outlink,
 #define FF_INLINK_IDX(link)  ((int)((link)->dstpad - (link)->dst->input_pads))
 #define FF_OUTLINK_IDX(link) ((int)((link)->srcpad - (link)->src->output_pads))
 
-int ff_buffersink_read_compat(AVFilterContext *ctx, AVFilterBufferRef **buf);
-int ff_buffersink_read_samples_compat(AVFilterContext *ctx, AVFilterBufferRef **pbuf,
-                                      int nb_samples);
 /**
  * Send a frame of data to the next filter.
  *