---
 libavresample/avresample.h |  54 +++++++++++++++++++++
 libavresample/utils.c      | 118 +++++++++++++++++++++++++++++++++++++++++++++
 libavutil/error.h          |   2 +
 3 files changed, 174 insertions(+)

diff --git a/libavresample/avresample.h b/libavresample/avresample.h
index 3358628..702a767 100644
--- a/libavresample/avresample.h
+++ b/libavresample/avresample.h
@@ -96,6 +96,7 @@
 #include "libavutil/avutil.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/dict.h"
+#include "libavutil/frame.h"
 #include "libavutil/log.h"
 
 #include "libavresample/version.h"
@@ -410,6 +411,59 @@ int avresample_available(AVAudioResampleContext *avr);
  */
 int avresample_read(AVAudioResampleContext *avr, uint8_t **output, int 
nb_samples);
 
+
+
+/**
+ * Convert the samples in the input AVFrame and write them to the output 
AVFrame.
+ *
+ * Input and output AVFrames must have channel_layout, sample_rate and format 
set.
+ *
+ * The upper bound on the number of output samples is given by
+ * avresample_available() + (avresample_get_delay() + number of input samples) 
*
+ * output sample rate / input sample rate.
+ *
+ * If the output AVFrame does not have the data pointers allocated a the 
nb_samples
+ * will be set as described above and av_frame_get_buffer() will be called.
+ *
+ * The output AVFrame can be NULL or have fewer allocated samples than 
required.
+ *
+ * In this case, any remaining samples not written to the output will be added
+ * to an internal FIFO buffer, to be returned at the next call to this function
+ * or to avresample_convert() or to avresample_read().
+ *
+ * If converting sample rate, there may be data remaining in the internal
+ * resampling delay buffer. avresample_get_delay() tells the number of 
remaining
+ * samples. To get this data as output, call this function or 
avresample_convert()
+ * with NULL input.
+ *
+ * At the end of the conversion process, there may be data remaining in the
+ * internal FIFO buffer. avresample_available() tells the number of remaining
+ * samples. To get this data as output, either call this function or 
avresample_convert()
+ * with NULL input or call avresample_read().
+ *
+ * If the AVAudioResampleContext configuration does not match the output and 
input AVFrame
+ * settings the conversion does not take place and depending on which AVFrame 
is not
+ * matching AVERROR_OUTPUT_CHANGED, AVERROR_INPUT_CHANGED or
+ * AVERROR_OUTPUT_CHANGED|AVERROR_INPUT_CHANGED is returned.
+ *
+ * @see avresample_available()
+ * @see avresample_convert()
+ * @see avresample_read()
+ * @see avresample_get_delay()
+ *
+ * @param avr             audio resample context
+ * @param output          output AVFrame
+ * @param input           input AVFrame
+ * @return                number of samples written to the output buffer,
+ *                        not including converted samples added to the internal
+ *                        output FIFO or an AVERROR.
+ */
+int avresample_convert_frame(AVAudioResampleContext *avr,
+                             AVFrame *output, AVFrame *input);
+
+int avresample_config(AVAudioResampleContext *avr, AVFrame *out, AVFrame *in,
+                      AVDictionary **opts);
+
 /**
  * @}
  */
diff --git a/libavresample/utils.c b/libavresample/utils.c
index 35bee42..37d9a63 100644
--- a/libavresample/utils.c
+++ b/libavresample/utils.c
@@ -21,6 +21,7 @@
 #include "libavutil/common.h"
 #include "libavutil/dict.h"
 #include "libavutil/error.h"
+#include "libavutil/frame.h"
 #include "libavutil/log.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
@@ -506,6 +507,123 @@ int attribute_align_arg 
avresample_convert(AVAudioResampleContext *avr,
                                   current_buffer);
 }
 
+int avresample_config(AVAudioResampleContext *avr, AVFrame *out, AVFrame *in,
+                      AVDictionary **opts)
+{
+    int ret;
+
+    if (avresample_is_open(avr)) {
+        avresample_close(avr);
+    }
+
+    if (!out || !in)
+        return AVERROR(EINVAL);
+
+    avr->in_channel_layout  = in->channel_layout;
+    avr->out_channel_layout = out->channel_layout;
+    avr->in_sample_rate     = in->sample_rate;
+    avr->out_sample_rate    = out->sample_rate;
+    avr->in_sample_fmt      = in->format;
+    avr->out_sample_fmt     = out->format;
+
+    if ((ret = av_opt_set_dict(avr, opts)) < 0)
+        return ret;
+
+    return avresample_open(avr);
+}
+
+static int config_changed(AVAudioResampleContext *avr,
+                          AVFrame *out, AVFrame *in)
+{
+    int ret = 0;
+
+    if (in) {
+        if (avr->in_channel_layout != in->channel_layout ||
+            avr->in_sample_rate    != in->sample_rate ||
+            avr->in_sample_fmt     != in->format) {
+            ret |= AVERROR_INPUT_CHANGED;
+        }
+    }
+
+    if (out) {
+        if (avr->out_channel_layout != out->channel_layout ||
+            avr->out_sample_rate    != out->sample_rate ||
+            avr->out_sample_fmt     != out->format) {
+            ret |= AVERROR_OUTPUT_CHANGED;
+        }
+    }
+
+    return ret;
+}
+
+static inline int convert_frame(AVAudioResampleContext *avr,
+                                AVFrame *out, AVFrame *in)
+{
+    int ret;
+    uint8_t **out_data = NULL, **in_data = NULL;
+    int out_linesize = 0, in_linesize = 0;
+    int out_nb_samples = 0, in_nb_samples = 0;
+
+    if (out) {
+        out_data       = out->extended_data;
+        out_linesize   = out->linesize[0];
+        out_nb_samples = out->nb_samples;
+    }
+
+    if (in) {
+        in_data       = in->extended_data;
+        in_linesize   = in->linesize[0];
+        in_nb_samples = in->nb_samples;
+    }
+
+    ret = avresample_convert(avr, out_data, out_linesize,
+                             out_nb_samples,
+                             in_data, in_linesize,
+                             in_nb_samples);
+
+    if (ret > 0) {
+        out->nb_samples = ret;
+        return 0;
+    }
+
+    return ret;
+}
+
+static inline int output_frame_samples(AVAudioResampleContext *avr,
+                                       AVFrame *out, AVFrame *in)
+{
+    return avresample_available(avr) +
+           (avresample_get_delay(avr) + in->nb_samples) *
+           out->sample_rate / in->sample_rate;
+}
+
+int avresample_convert_frame(AVAudioResampleContext *avr,
+                             AVFrame *out, AVFrame *in)
+{
+    int ret;
+
+    if (!avresample_is_open(avr)) {
+        if ((ret = avresample_config(avr, out, in, NULL)) < 0)
+            return ret;
+        if ((ret = avresample_open(avr)) < 0)
+            return ret;
+    } else {
+        // return as is or reconfigure for input changes?
+        if ((ret = config_changed(avr, out, in)))
+            return ret;
+    }
+
+    if (out && !out->linesize[0]) {
+        out->nb_samples = output_frame_samples(avr, out, in);
+        if ((ret = av_frame_get_buffer(out, 0)) < 0) {
+            avresample_close(avr);
+            return ret;
+        }
+    }
+
+    return convert_frame(avr, out, in);
+}
+
 int avresample_get_matrix(AVAudioResampleContext *avr, double *matrix,
                           int stride)
 {
diff --git a/libavutil/error.h b/libavutil/error.h
index 268a032..0a95d2e 100644
--- a/libavutil/error.h
+++ b/libavutil/error.h
@@ -60,6 +60,8 @@
 #define AVERROR_BUG                (-0x5fb8aabe) ///< Bug detected, please 
report the issue
 #define AVERROR_UNKNOWN            (-0x31b4b1ab) ///< Unknown error, typically 
from an external library
 #define AVERROR_EXPERIMENTAL       (-0x2bb2afa8) ///< Requested feature is 
flagged experimental. Set strict_std_compliance if you really want to use it.
+#define AVERROR_INPUT_CHANGED      (-0x636e6701) ///< Input changed between 
calls. Reconfiguration is required.
+#define AVERROR_OUTPUT_CHANGED     (-0x636e6702) ///< Output changed between 
calls. Reconfiguration is required.
 
 /**
  * Put a description of the AVERROR code errnum in errbuf.
-- 
1.8.5.2 (Apple Git-48)

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