]> git.sesse.net Git - ffmpeg/blobdiff - libavresample/utils.c
decode: fix the code reducing cropping to preserve alignment
[ffmpeg] / libavresample / utils.c
index e533760abc3b97073634d3d642f8563aeef23758..bab2153b4b1e3dc336796384424aa4a005a84867 100644 (file)
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#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"
 
 #include "avresample.h"
-#include "audio_data.h"
 #include "internal.h"
+#include "audio_data.h"
+#include "audio_convert.h"
+#include "audio_mix.h"
+#include "resample.h"
 
 int avresample_open(AVAudioResampleContext *avr)
 {
     int ret;
 
+    if (avresample_is_open(avr)) {
+        av_log(avr, AV_LOG_ERROR, "The resampling context is already open.\n");
+        return AVERROR(EINVAL);
+    }
+
     /* set channel mixing parameters */
     avr->in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
     if (avr->in_channels <= 0 || avr->in_channels > AVRESAMPLE_MAX_CHANNELS) {
@@ -48,40 +58,122 @@ int avresample_open(AVAudioResampleContext *avr)
     avr->resample_channels = FFMIN(avr->in_channels, avr->out_channels);
     avr->downmix_needed    = avr->in_channels  > avr->out_channels;
     avr->upmix_needed      = avr->out_channels > avr->in_channels ||
-                             avr->am->matrix                      ||
-                             (avr->out_channels == avr->in_channels &&
-                              avr->in_channel_layout != avr->out_channel_layout);
+                             (!avr->downmix_needed && (avr->mix_matrix ||
+                              avr->in_channel_layout != avr->out_channel_layout));
     avr->mixing_needed     = avr->downmix_needed || avr->upmix_needed;
 
     /* set resampling parameters */
     avr->resample_needed   = avr->in_sample_rate != avr->out_sample_rate ||
                              avr->force_resampling;
 
+    /* select internal sample format if not specified by the user */
+    if (avr->internal_sample_fmt == AV_SAMPLE_FMT_NONE &&
+        (avr->mixing_needed || avr->resample_needed)) {
+        enum AVSampleFormat  in_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
+        enum AVSampleFormat out_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
+        int max_bps = FFMAX(av_get_bytes_per_sample(in_fmt),
+                            av_get_bytes_per_sample(out_fmt));
+        if (max_bps <= 2) {
+            avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;
+        } else if (avr->mixing_needed) {
+            avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
+        } else {
+            if (max_bps <= 4) {
+                if (in_fmt  == AV_SAMPLE_FMT_S32P ||
+                    out_fmt == AV_SAMPLE_FMT_S32P) {
+                    if (in_fmt  == AV_SAMPLE_FMT_FLTP ||
+                        out_fmt == AV_SAMPLE_FMT_FLTP) {
+                        /* if one is s32 and the other is flt, use dbl */
+                        avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
+                    } else {
+                        /* if one is s32 and the other is s32, s16, or u8, use s32 */
+                        avr->internal_sample_fmt = AV_SAMPLE_FMT_S32P;
+                    }
+                } else {
+                    /* if one is flt and the other is flt, s16 or u8, use flt */
+                    avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
+                }
+            } else {
+                /* if either is dbl, use dbl */
+                avr->internal_sample_fmt = AV_SAMPLE_FMT_DBLP;
+            }
+        }
+        av_log(avr, AV_LOG_DEBUG, "Using %s as internal sample format\n",
+               av_get_sample_fmt_name(avr->internal_sample_fmt));
+    }
+
+    /* we may need to add an extra conversion in order to remap channels if
+       the output format is not planar */
+    if (avr->use_channel_map && !avr->mixing_needed && !avr->resample_needed &&
+        !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels)) {
+        avr->internal_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
+    }
+
     /* set sample format conversion parameters */
-    /* override user-requested internal format to avoid unexpected failures
-       TODO: support more internal formats */
-    if (avr->resample_needed && avr->internal_sample_fmt != AV_SAMPLE_FMT_S16P) {
-        av_log(avr, AV_LOG_WARNING, "Using s16p as internal sample format\n");
-        avr->internal_sample_fmt = AV_SAMPLE_FMT_S16P;
-    } else if (avr->mixing_needed &&
-               avr->internal_sample_fmt != AV_SAMPLE_FMT_S16P &&
-               avr->internal_sample_fmt != AV_SAMPLE_FMT_FLTP) {
-        av_log(avr, AV_LOG_WARNING, "Using fltp as internal sample format\n");
-        avr->internal_sample_fmt = AV_SAMPLE_FMT_FLTP;
-    }
-    if (avr->in_channels == 1)
-        avr->in_sample_fmt = av_get_planar_sample_fmt(avr->in_sample_fmt);
-    if (avr->out_channels == 1)
-        avr->out_sample_fmt = av_get_planar_sample_fmt(avr->out_sample_fmt);
-    avr->in_convert_needed = (avr->resample_needed || avr->mixing_needed) &&
-                              avr->in_sample_fmt != avr->internal_sample_fmt;
     if (avr->resample_needed || avr->mixing_needed)
+        avr->in_convert_needed = avr->in_sample_fmt != avr->internal_sample_fmt;
+    else
+        avr->in_convert_needed = avr->use_channel_map &&
+                                 !ff_sample_fmt_is_planar(avr->out_sample_fmt, avr->out_channels);
+
+    if (avr->resample_needed || avr->mixing_needed || avr->in_convert_needed)
         avr->out_convert_needed = avr->internal_sample_fmt != avr->out_sample_fmt;
     else
         avr->out_convert_needed = avr->in_sample_fmt != avr->out_sample_fmt;
 
+    avr->in_copy_needed = !avr->in_convert_needed && (avr->mixing_needed ||
+                          (avr->use_channel_map && avr->resample_needed));
+
+    if (avr->use_channel_map) {
+        if (avr->in_copy_needed) {
+            avr->remap_point = REMAP_IN_COPY;
+            av_log(avr, AV_LOG_TRACE, "remap channels during in_copy\n");
+        } else if (avr->in_convert_needed) {
+            avr->remap_point = REMAP_IN_CONVERT;
+            av_log(avr, AV_LOG_TRACE, "remap channels during in_convert\n");
+        } else if (avr->out_convert_needed) {
+            avr->remap_point = REMAP_OUT_CONVERT;
+            av_log(avr, AV_LOG_TRACE, "remap channels during out_convert\n");
+        } else {
+            avr->remap_point = REMAP_OUT_COPY;
+            av_log(avr, AV_LOG_TRACE, "remap channels during out_copy\n");
+        }
+
+#ifdef DEBUG
+        {
+            int ch;
+            av_log(avr, AV_LOG_TRACE, "output map: ");
+            if (avr->ch_map_info.do_remap)
+                for (ch = 0; ch < avr->in_channels; ch++)
+                    av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_map[ch]);
+            else
+                av_log(avr, AV_LOG_TRACE, "n/a");
+            av_log(avr, AV_LOG_TRACE, "\n");
+            av_log(avr, AV_LOG_TRACE, "copy map:   ");
+            if (avr->ch_map_info.do_copy)
+                for (ch = 0; ch < avr->in_channels; ch++)
+                    av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_copy[ch]);
+            else
+                av_log(avr, AV_LOG_TRACE, "n/a");
+            av_log(avr, AV_LOG_TRACE, "\n");
+            av_log(avr, AV_LOG_TRACE, "zero map:   ");
+            if (avr->ch_map_info.do_zero)
+                for (ch = 0; ch < avr->in_channels; ch++)
+                    av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.channel_zero[ch]);
+            else
+                av_log(avr, AV_LOG_TRACE, "n/a");
+            av_log(avr, AV_LOG_TRACE, "\n");
+            av_log(avr, AV_LOG_TRACE, "input map:  ");
+            for (ch = 0; ch < avr->in_channels; ch++)
+                av_log(avr, AV_LOG_TRACE, " % 2d", avr->ch_map_info.input_map[ch]);
+            av_log(avr, AV_LOG_TRACE, "\n");
+        }
+#endif
+    } else
+        avr->remap_point = REMAP_NONE;
+
     /* allocate buffers */
-    if (avr->mixing_needed || avr->in_convert_needed) {
+    if (avr->in_copy_needed || avr->in_convert_needed) {
         avr->in_buffer = ff_audio_data_alloc(FFMAX(avr->in_channels, avr->out_channels),
                                              0, avr->internal_sample_fmt,
                                              "in_buffer");
@@ -92,7 +184,7 @@ int avresample_open(AVAudioResampleContext *avr)
     }
     if (avr->resample_needed) {
         avr->resample_out_buffer = ff_audio_data_alloc(avr->out_channels,
-                                                       0, avr->internal_sample_fmt,
+                                                       1024, avr->internal_sample_fmt,
                                                        "resample_out_buffer");
         if (!avr->resample_out_buffer) {
             ret = AVERROR(EINVAL);
@@ -117,7 +209,9 @@ int avresample_open(AVAudioResampleContext *avr)
     /* setup contexts */
     if (avr->in_convert_needed) {
         avr->ac_in = ff_audio_convert_alloc(avr, avr->internal_sample_fmt,
-                                            avr->in_sample_fmt, avr->in_channels);
+                                            avr->in_sample_fmt, avr->in_channels,
+                                            avr->in_sample_rate,
+                                            avr->remap_point == REMAP_IN_CONVERT);
         if (!avr->ac_in) {
             ret = AVERROR(ENOMEM);
             goto error;
@@ -130,7 +224,9 @@ int avresample_open(AVAudioResampleContext *avr)
         else
             src_fmt = avr->in_sample_fmt;
         avr->ac_out = ff_audio_convert_alloc(avr, avr->out_sample_fmt, src_fmt,
-                                             avr->out_channels);
+                                             avr->out_channels,
+                                             avr->out_sample_rate,
+                                             avr->remap_point == REMAP_OUT_CONVERT);
         if (!avr->ac_out) {
             ret = AVERROR(ENOMEM);
             goto error;
@@ -144,9 +240,11 @@ int avresample_open(AVAudioResampleContext *avr)
         }
     }
     if (avr->mixing_needed) {
-        ret = ff_audio_mix_init(avr);
-        if (ret < 0)
+        avr->am = ff_audio_mix_alloc(avr);
+        if (!avr->am) {
+            ret = AVERROR(ENOMEM);
             goto error;
+        }
     }
 
     return 0;
@@ -156,6 +254,11 @@ error:
     return ret;
 }
 
+int avresample_is_open(AVAudioResampleContext *avr)
+{
+    return !!avr->out_fifo;
+}
+
 void avresample_close(AVAudioResampleContext *avr)
 {
     ff_audio_data_free(&avr->in_buffer);
@@ -163,11 +266,13 @@ void avresample_close(AVAudioResampleContext *avr)
     ff_audio_data_free(&avr->out_buffer);
     av_audio_fifo_free(avr->out_fifo);
     avr->out_fifo = NULL;
-    av_freep(&avr->ac_in);
-    av_freep(&avr->ac_out);
+    ff_audio_convert_free(&avr->ac_in);
+    ff_audio_convert_free(&avr->ac_out);
     ff_audio_resample_free(&avr->resample);
-    ff_audio_mix_close(avr->am);
-    return;
+    ff_audio_mix_free(&avr->am);
+    av_freep(&avr->mix_matrix);
+
+    avr->use_channel_map = 0;
 }
 
 void avresample_free(AVAudioResampleContext **avr)
@@ -175,7 +280,6 @@ void avresample_free(AVAudioResampleContext **avr)
     if (!*avr)
         return;
     avresample_close(*avr);
-    av_freep(&(*avr)->am);
     av_opt_free(*avr);
     av_freep(avr);
 }
@@ -191,7 +295,7 @@ static int handle_buffered_output(AVAudioResampleContext *avr,
             /* if there are any samples in the output FIFO or if the
                user-supplied output buffer is not large enough for all samples,
                we add to the output FIFO */
-            av_dlog(avr, "[FIFO] add %s to out_fifo\n", converted->name);
+            av_log(avr, AV_LOG_TRACE, "[FIFO] add %s to out_fifo\n", converted->name);
             ret = ff_audio_data_add_to_fifo(avr->out_fifo, converted, 0,
                                             converted->nb_samples);
             if (ret < 0)
@@ -201,34 +305,38 @@ static int handle_buffered_output(AVAudioResampleContext *avr,
         /* if the user specified an output buffer, read samples from the output
            FIFO to the user output */
         if (output && output->allocated_samples > 0) {
-            av_dlog(avr, "[FIFO] read from out_fifo to output\n");
-            av_dlog(avr, "[end conversion]\n");
+            av_log(avr, AV_LOG_TRACE, "[FIFO] read from out_fifo to output\n");
+            av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
             return ff_audio_data_read_from_fifo(avr->out_fifo, output,
                                                 output->allocated_samples);
         }
     } else if (converted) {
         /* copy directly to output if it is large enough or there is not any
            data in the output FIFO */
-        av_dlog(avr, "[copy] %s to output\n", converted->name);
+        av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", converted->name);
         output->nb_samples = 0;
-        ret = ff_audio_data_copy(output, converted);
+        ret = ff_audio_data_copy(output, converted,
+                                 avr->remap_point == REMAP_OUT_COPY ?
+                                 &avr->ch_map_info : NULL);
         if (ret < 0)
             return ret;
-        av_dlog(avr, "[end conversion]\n");
+        av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
         return output->nb_samples;
     }
-    av_dlog(avr, "[end conversion]\n");
+    av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
     return 0;
 }
 
-int avresample_convert(AVAudioResampleContext *avr, void **output,
-                       int out_plane_size, int out_samples, void **input,
-                       int in_plane_size, int in_samples)
+int attribute_align_arg avresample_convert(AVAudioResampleContext *avr,
+                                           uint8_t **output, int out_plane_size,
+                                           int out_samples,
+                                           uint8_t * const *input,
+                                           int in_plane_size, int in_samples)
 {
     AudioData input_buffer;
     AudioData output_buffer;
     AudioData *current_buffer;
-    int ret;
+    int ret, direct_output;
 
     /* reset internal buffers */
     if (avr->in_buffer) {
@@ -247,9 +355,10 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
                                    avr->out_buffer->allocated_channels);
     }
 
-    av_dlog(avr, "[start conversion]\n");
+    av_log(avr, AV_LOG_TRACE, "[start conversion]\n");
 
     /* initialize output_buffer with output data */
+    direct_output = output && av_audio_fifo_size(avr->out_fifo) == 0;
     if (output) {
         ret = ff_audio_data_init(&output_buffer, output, out_plane_size,
                                  avr->out_channels, out_samples,
@@ -269,15 +378,28 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
         current_buffer = &input_buffer;
 
         if (avr->upmix_needed && !avr->in_convert_needed && !avr->resample_needed &&
-            !avr->out_convert_needed && output && out_samples >= in_samples) {
+            !avr->out_convert_needed && direct_output && out_samples >= in_samples) {
             /* in some rare cases we can copy input to output and upmix
                directly in the output buffer */
-            av_dlog(avr, "[copy] %s to output\n", current_buffer->name);
-            ret = ff_audio_data_copy(&output_buffer, current_buffer);
+            av_log(avr, AV_LOG_TRACE, "[copy] %s to output\n", current_buffer->name);
+            ret = ff_audio_data_copy(&output_buffer, current_buffer,
+                                     avr->remap_point == REMAP_OUT_COPY ?
+                                     &avr->ch_map_info : NULL);
             if (ret < 0)
                 return ret;
             current_buffer = &output_buffer;
-        } else if (avr->mixing_needed || avr->in_convert_needed) {
+        } else if (avr->remap_point == REMAP_OUT_COPY &&
+                   (!direct_output || out_samples < in_samples)) {
+            /* if remapping channels during output copy, we may need to
+             * use an intermediate buffer in order to remap before adding
+             * samples to the output fifo */
+            av_log(avr, AV_LOG_TRACE, "[copy] %s to out_buffer\n", current_buffer->name);
+            ret = ff_audio_data_copy(avr->out_buffer, current_buffer,
+                                     &avr->ch_map_info);
+            if (ret < 0)
+                return ret;
+            current_buffer = avr->out_buffer;
+        } else if (avr->in_copy_needed || avr->in_convert_needed) {
             /* if needed, copy or convert input to in_buffer, and downmix if
                applicable */
             if (avr->in_convert_needed) {
@@ -285,20 +407,22 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
                                             current_buffer->nb_samples);
                 if (ret < 0)
                     return ret;
-                av_dlog(avr, "[convert] %s to in_buffer\n", current_buffer->name);
-                ret = ff_audio_convert(avr->ac_in, avr->in_buffer, current_buffer,
-                                       current_buffer->nb_samples);
+                av_log(avr, AV_LOG_TRACE, "[convert] %s to in_buffer\n", current_buffer->name);
+                ret = ff_audio_convert(avr->ac_in, avr->in_buffer,
+                                       current_buffer);
                 if (ret < 0)
                     return ret;
             } else {
-                av_dlog(avr, "[copy] %s to in_buffer\n", current_buffer->name);
-                ret = ff_audio_data_copy(avr->in_buffer, current_buffer);
+                av_log(avr, AV_LOG_TRACE, "[copy] %s to in_buffer\n", current_buffer->name);
+                ret = ff_audio_data_copy(avr->in_buffer, current_buffer,
+                                         avr->remap_point == REMAP_IN_COPY ?
+                                         &avr->ch_map_info : NULL);
                 if (ret < 0)
                     return ret;
             }
             ff_audio_data_set_channels(avr->in_buffer, avr->in_channels);
             if (avr->downmix_needed) {
-                av_dlog(avr, "[downmix] in_buffer\n");
+                av_log(avr, AV_LOG_TRACE, "[downmix] in_buffer\n");
                 ret = ff_audio_mix(avr->am, avr->in_buffer);
                 if (ret < 0)
                     return ret;
@@ -315,22 +439,22 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
 
     if (avr->resample_needed) {
         AudioData *resample_out;
-        int consumed = 0;
 
-        if (!avr->out_convert_needed && output && out_samples > 0)
+        if (!avr->out_convert_needed && direct_output && out_samples > 0)
             resample_out = &output_buffer;
         else
             resample_out = avr->resample_out_buffer;
-        av_dlog(avr, "[resample] %s to %s\n", current_buffer->name,
+        av_log(avr, AV_LOG_TRACE, "[resample] %s to %s\n",
+                current_buffer ? current_buffer->name : "null",
                 resample_out->name);
         ret = ff_audio_resample(avr->resample, resample_out,
-                                current_buffer, &consumed);
+                                current_buffer);
         if (ret < 0)
             return ret;
 
         /* if resampling did not produce any samples, just return 0 */
         if (resample_out->nb_samples == 0) {
-            av_dlog(avr, "[end conversion]\n");
+            av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
             return 0;
         }
 
@@ -338,7 +462,7 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
     }
 
     if (avr->upmix_needed) {
-        av_dlog(avr, "[upmix] %s\n", current_buffer->name);
+        av_log(avr, AV_LOG_TRACE, "[upmix] %s\n", current_buffer->name);
         ret = ff_audio_mix(avr->am, current_buffer);
         if (ret < 0)
             return ret;
@@ -346,36 +470,279 @@ int avresample_convert(AVAudioResampleContext *avr, void **output,
 
     /* if we resampled or upmixed directly to output, return here */
     if (current_buffer == &output_buffer) {
-        av_dlog(avr, "[end conversion]\n");
+        av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
         return current_buffer->nb_samples;
     }
 
     if (avr->out_convert_needed) {
-        if (output && out_samples >= current_buffer->nb_samples) {
+        if (direct_output && out_samples >= current_buffer->nb_samples) {
             /* convert directly to output */
-            av_dlog(avr, "[convert] %s to output\n", current_buffer->name);
-            ret = ff_audio_convert(avr->ac_out, &output_buffer, current_buffer,
-                                   current_buffer->nb_samples);
+            av_log(avr, AV_LOG_TRACE, "[convert] %s to output\n", current_buffer->name);
+            ret = ff_audio_convert(avr->ac_out, &output_buffer, current_buffer);
             if (ret < 0)
                 return ret;
 
-            av_dlog(avr, "[end conversion]\n");
+            av_log(avr, AV_LOG_TRACE, "[end conversion]\n");
             return output_buffer.nb_samples;
         } else {
             ret = ff_audio_data_realloc(avr->out_buffer,
                                         current_buffer->nb_samples);
             if (ret < 0)
                 return ret;
-            av_dlog(avr, "[convert] %s to out_buffer\n", current_buffer->name);
+            av_log(avr, AV_LOG_TRACE, "[convert] %s to out_buffer\n", current_buffer->name);
             ret = ff_audio_convert(avr->ac_out, avr->out_buffer,
-                                   current_buffer, current_buffer->nb_samples);
+                                   current_buffer);
             if (ret < 0)
                 return ret;
             current_buffer = avr->out_buffer;
         }
     }
 
-    return handle_buffered_output(avr, &output_buffer, current_buffer);
+    return handle_buffered_output(avr, output ? &output_buffer : NULL,
+                                  current_buffer);
+}
+
+int avresample_config(AVAudioResampleContext *avr, AVFrame *out, AVFrame *in)
+{
+    if (avresample_is_open(avr)) {
+        avresample_close(avr);
+    }
+
+    if (in) {
+        avr->in_channel_layout  = in->channel_layout;
+        avr->in_sample_rate     = in->sample_rate;
+        avr->in_sample_fmt      = in->format;
+    }
+
+    if (out) {
+        avr->out_channel_layout = out->channel_layout;
+        avr->out_sample_rate    = out->sample_rate;
+        avr->out_sample_fmt     = out->format;
+    }
+
+    return 0;
+}
+
+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) {
+        if (out)
+            out->nb_samples = 0;
+        return ret;
+    }
+
+    if (out)
+        out->nb_samples = ret;
+
+    return 0;
+}
+
+static inline int available_samples(AVFrame *out)
+{
+    int samples;
+    int bytes_per_sample = av_get_bytes_per_sample(out->format);
+    if (!bytes_per_sample)
+        return AVERROR(EINVAL);
+
+    samples = out->linesize[0] / bytes_per_sample;
+    if (av_sample_fmt_is_planar(out->format)) {
+        return samples;
+    } else {
+        int channels = av_get_channel_layout_nb_channels(out->channel_layout);
+        return samples / channels;
+    }
+}
+
+int avresample_convert_frame(AVAudioResampleContext *avr,
+                             AVFrame *out, AVFrame *in)
+{
+    int ret, setup = 0;
+
+    if (!avresample_is_open(avr)) {
+        if ((ret = avresample_config(avr, out, in)) < 0)
+            return ret;
+        if ((ret = avresample_open(avr)) < 0)
+            return ret;
+        setup = 1;
+    } else {
+        // return as is or reconfigure for input changes?
+        if ((ret = config_changed(avr, out, in)))
+            return ret;
+    }
+
+    if (out) {
+        if (!out->linesize[0]) {
+            out->nb_samples = avresample_get_out_samples(avr, in->nb_samples);
+            if ((ret = av_frame_get_buffer(out, 0)) < 0) {
+                if (setup)
+                    avresample_close(avr);
+                return ret;
+            }
+        } else {
+            if (!out->nb_samples)
+                out->nb_samples = available_samples(out);
+        }
+    }
+
+    return convert_frame(avr, out, in);
+}
+
+int avresample_get_matrix(AVAudioResampleContext *avr, double *matrix,
+                          int stride)
+{
+    int in_channels, out_channels, i, o;
+
+    if (avr->am)
+        return ff_audio_mix_get_matrix(avr->am, matrix, stride);
+
+    in_channels  = av_get_channel_layout_nb_channels(avr->in_channel_layout);
+    out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
+
+    if ( in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS ||
+        out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
+        av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
+        return AVERROR(EINVAL);
+    }
+
+    if (!avr->mix_matrix) {
+        av_log(avr, AV_LOG_ERROR, "matrix is not set\n");
+        return AVERROR(EINVAL);
+    }
+
+    for (o = 0; o < out_channels; o++)
+        for (i = 0; i < in_channels; i++)
+            matrix[o * stride + i] = avr->mix_matrix[o * in_channels + i];
+
+    return 0;
+}
+
+int avresample_set_matrix(AVAudioResampleContext *avr, const double *matrix,
+                          int stride)
+{
+    int in_channels, out_channels, i, o;
+
+    if (avr->am)
+        return ff_audio_mix_set_matrix(avr->am, matrix, stride);
+
+    in_channels  = av_get_channel_layout_nb_channels(avr->in_channel_layout);
+    out_channels = av_get_channel_layout_nb_channels(avr->out_channel_layout);
+
+    if ( in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS ||
+        out_channels <= 0 || out_channels > AVRESAMPLE_MAX_CHANNELS) {
+        av_log(avr, AV_LOG_ERROR, "Invalid channel layouts\n");
+        return AVERROR(EINVAL);
+    }
+
+    if (avr->mix_matrix)
+        av_freep(&avr->mix_matrix);
+    avr->mix_matrix = av_malloc(in_channels * out_channels *
+                                sizeof(*avr->mix_matrix));
+    if (!avr->mix_matrix)
+        return AVERROR(ENOMEM);
+
+    for (o = 0; o < out_channels; o++)
+        for (i = 0; i < in_channels; i++)
+            avr->mix_matrix[o * in_channels + i] = matrix[o * stride + i];
+
+    return 0;
+}
+
+int avresample_set_channel_mapping(AVAudioResampleContext *avr,
+                                   const int *channel_map)
+{
+    ChannelMapInfo *info = &avr->ch_map_info;
+    int in_channels, ch, i;
+
+    in_channels = av_get_channel_layout_nb_channels(avr->in_channel_layout);
+    if (in_channels <= 0 ||  in_channels > AVRESAMPLE_MAX_CHANNELS) {
+        av_log(avr, AV_LOG_ERROR, "Invalid input channel layout\n");
+        return AVERROR(EINVAL);
+    }
+
+    memset(info, 0, sizeof(*info));
+    memset(info->input_map, -1, sizeof(info->input_map));
+
+    for (ch = 0; ch < in_channels; ch++) {
+        if (channel_map[ch] >= in_channels) {
+            av_log(avr, AV_LOG_ERROR, "Invalid channel map\n");
+            return AVERROR(EINVAL);
+        }
+        if (channel_map[ch] < 0) {
+            info->channel_zero[ch] =  1;
+            info->channel_map[ch]  = -1;
+            info->do_zero          =  1;
+        } else if (info->input_map[channel_map[ch]] >= 0) {
+            info->channel_copy[ch] = info->input_map[channel_map[ch]];
+            info->channel_map[ch]  = -1;
+            info->do_copy          =  1;
+        } else {
+            info->channel_map[ch]            = channel_map[ch];
+            info->input_map[channel_map[ch]] = ch;
+            info->do_remap                   =  1;
+        }
+    }
+    /* Fill-in unmapped input channels with unmapped output channels.
+       This is used when remapping during conversion from interleaved to
+       planar format. */
+    for (ch = 0, i = 0; ch < in_channels && i < in_channels; ch++, i++) {
+        while (ch < in_channels && info->input_map[ch] >= 0)
+            ch++;
+        while (i < in_channels && info->channel_map[i] >= 0)
+            i++;
+        if (ch >= in_channels || i >= in_channels)
+            break;
+        info->input_map[ch] = i;
+    }
+
+    avr->use_channel_map = 1;
+    return 0;
 }
 
 int avresample_available(AVAudioResampleContext *avr)
@@ -383,11 +750,30 @@ int avresample_available(AVAudioResampleContext *avr)
     return av_audio_fifo_size(avr->out_fifo);
 }
 
-int avresample_read(AVAudioResampleContext *avr, void **output, int nb_samples)
+int avresample_get_out_samples(AVAudioResampleContext *avr, int in_nb_samples)
+{
+    int64_t samples = avresample_get_delay(avr) + (int64_t)in_nb_samples;
+
+    if (avr->resample_needed) {
+        samples = av_rescale_rnd(samples,
+                                 avr->out_sample_rate,
+                                 avr->in_sample_rate,
+                                 AV_ROUND_UP);
+    }
+
+    samples += avresample_available(avr);
+
+    if (samples > INT_MAX)
+        return AVERROR(EINVAL);
+
+    return samples;
+}
+
+int avresample_read(AVAudioResampleContext *avr, uint8_t **output, int nb_samples)
 {
     if (!output)
         return av_audio_fifo_drain(avr->out_fifo, nb_samples);
-    return av_audio_fifo_read(avr->out_fifo, output, nb_samples);
+    return av_audio_fifo_read(avr->out_fifo, (void**)output, nb_samples);
 }
 
 unsigned avresample_version(void)