yading@10: /*
yading@10:  * Copyright (c) 2011 Stefano Sabatini
yading@10:  * Copyright (c) 2011 Mina Nagy Zaki
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * resampling audio filter
yading@10:  */
yading@10: 
yading@10: #include "libavutil/avstring.h"
yading@10: #include "libavutil/channel_layout.h"
yading@10: #include "libavutil/opt.h"
yading@10: #include "libavutil/samplefmt.h"
yading@10: #include "libavutil/avassert.h"
yading@10: #include "libswresample/swresample.h"
yading@10: #include "avfilter.h"
yading@10: #include "audio.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: typedef struct {
yading@10:     const AVClass *class;
yading@10:     int sample_rate_arg;
yading@10:     double ratio;
yading@10:     struct SwrContext *swr;
yading@10:     int64_t next_pts;
yading@10:     int req_fullfilled;
yading@10: } AResampleContext;
yading@10: 
yading@10: static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
yading@10: {
yading@10:     AResampleContext *aresample = ctx->priv;
yading@10:     int ret = 0;
yading@10: 
yading@10:     aresample->next_pts = AV_NOPTS_VALUE;
yading@10:     aresample->swr = swr_alloc();
yading@10:     if (!aresample->swr) {
yading@10:         ret = AVERROR(ENOMEM);
yading@10:         goto end;
yading@10:     }
yading@10: 
yading@10:     if (opts) {
yading@10:         AVDictionaryEntry *e = NULL;
yading@10: 
yading@10:         while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
yading@10:             const char *token = e->key;
yading@10:             const char *value = e->value;
yading@10:             if ((ret = av_opt_set(aresample->swr, token, value, 0)) < 0)
yading@10:                 goto end;
yading@10:         }
yading@10:         av_dict_free(opts);
yading@10:     }
yading@10:     if (aresample->sample_rate_arg > 0)
yading@10:         av_opt_set_int(aresample->swr, "osr", aresample->sample_rate_arg, 0);
yading@10: end:
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static av_cold void uninit(AVFilterContext *ctx)
yading@10: {
yading@10:     AResampleContext *aresample = ctx->priv;
yading@10:     swr_free(&aresample->swr);
yading@10: }
yading@10: 
yading@10: static int query_formats(AVFilterContext *ctx)
yading@10: {
yading@10:     AResampleContext *aresample = ctx->priv;
yading@10:     int out_rate                   = av_get_int(aresample->swr, "osr", NULL);
yading@10:     uint64_t out_layout            = av_get_int(aresample->swr, "ocl", NULL);
yading@10:     enum AVSampleFormat out_format = av_get_int(aresample->swr, "osf", NULL);
yading@10: 
yading@10:     AVFilterLink *inlink  = ctx->inputs[0];
yading@10:     AVFilterLink *outlink = ctx->outputs[0];
yading@10: 
yading@10:     AVFilterFormats        *in_formats      = ff_all_formats(AVMEDIA_TYPE_AUDIO);
yading@10:     AVFilterFormats        *out_formats;
yading@10:     AVFilterFormats        *in_samplerates  = ff_all_samplerates();
yading@10:     AVFilterFormats        *out_samplerates;
yading@10:     AVFilterChannelLayouts *in_layouts      = ff_all_channel_counts();
yading@10:     AVFilterChannelLayouts *out_layouts;
yading@10: 
yading@10:     ff_formats_ref  (in_formats,      &inlink->out_formats);
yading@10:     ff_formats_ref  (in_samplerates,  &inlink->out_samplerates);
yading@10:     ff_channel_layouts_ref(in_layouts,      &inlink->out_channel_layouts);
yading@10: 
yading@10:     if(out_rate > 0) {
yading@10:         out_samplerates = ff_make_format_list((int[]){ out_rate, -1 });
yading@10:     } else {
yading@10:         out_samplerates = ff_all_samplerates();
yading@10:     }
yading@10:     ff_formats_ref(out_samplerates, &outlink->in_samplerates);
yading@10: 
yading@10:     if(out_format != AV_SAMPLE_FMT_NONE) {
yading@10:         out_formats = ff_make_format_list((int[]){ out_format, -1 });
yading@10:     } else
yading@10:         out_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO);
yading@10:     ff_formats_ref(out_formats, &outlink->in_formats);
yading@10: 
yading@10:     if(out_layout) {
yading@10:         out_layouts = avfilter_make_format64_list((int64_t[]){ out_layout, -1 });
yading@10:     } else
yading@10:         out_layouts = ff_all_channel_counts();
yading@10:     ff_channel_layouts_ref(out_layouts, &outlink->in_channel_layouts);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: 
yading@10: static int config_output(AVFilterLink *outlink)
yading@10: {
yading@10:     int ret;
yading@10:     AVFilterContext *ctx = outlink->src;
yading@10:     AVFilterLink *inlink = ctx->inputs[0];
yading@10:     AResampleContext *aresample = ctx->priv;
yading@10:     int out_rate;
yading@10:     uint64_t out_layout;
yading@10:     enum AVSampleFormat out_format;
yading@10:     char inchl_buf[128], outchl_buf[128];
yading@10: 
yading@10:     aresample->swr = swr_alloc_set_opts(aresample->swr,
yading@10:                                         outlink->channel_layout, outlink->format, outlink->sample_rate,
yading@10:                                         inlink->channel_layout, inlink->format, inlink->sample_rate,
yading@10:                                         0, ctx);
yading@10:     if (!aresample->swr)
yading@10:         return AVERROR(ENOMEM);
yading@10:     if (!inlink->channel_layout)
yading@10:         av_opt_set_int(aresample->swr, "ich", inlink->channels, 0);
yading@10:     if (!outlink->channel_layout)
yading@10:         av_opt_set_int(aresample->swr, "och", outlink->channels, 0);
yading@10: 
yading@10:     ret = swr_init(aresample->swr);
yading@10:     if (ret < 0)
yading@10:         return ret;
yading@10: 
yading@10:     out_rate   = av_get_int(aresample->swr, "osr", NULL);
yading@10:     out_layout = av_get_int(aresample->swr, "ocl", NULL);
yading@10:     out_format = av_get_int(aresample->swr, "osf", NULL);
yading@10:     outlink->time_base = (AVRational) {1, out_rate};
yading@10: 
yading@10:     av_assert0(outlink->sample_rate == out_rate);
yading@10:     av_assert0(outlink->channel_layout == out_layout || !outlink->channel_layout);
yading@10:     av_assert0(outlink->format == out_format);
yading@10: 
yading@10:     aresample->ratio = (double)outlink->sample_rate / inlink->sample_rate;
yading@10: 
yading@10:     av_get_channel_layout_string(inchl_buf,  sizeof(inchl_buf),  inlink ->channels, inlink ->channel_layout);
yading@10:     av_get_channel_layout_string(outchl_buf, sizeof(outchl_buf), outlink->channels, outlink->channel_layout);
yading@10: 
yading@10:     av_log(ctx, AV_LOG_VERBOSE, "ch:%d chl:%s fmt:%s r:%dHz -> ch:%d chl:%s fmt:%s r:%dHz\n",
yading@10:            inlink ->channels, inchl_buf,  av_get_sample_fmt_name(inlink->format),  inlink->sample_rate,
yading@10:            outlink->channels, outchl_buf, av_get_sample_fmt_name(outlink->format), outlink->sample_rate);
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int filter_frame(AVFilterLink *inlink, AVFrame *insamplesref)
yading@10: {
yading@10:     AResampleContext *aresample = inlink->dst->priv;
yading@10:     const int n_in  = insamplesref->nb_samples;
yading@10:     int n_out       = n_in * aresample->ratio * 2 + 256;
yading@10:     AVFilterLink *const outlink = inlink->dst->outputs[0];
yading@10:     AVFrame *outsamplesref = ff_get_audio_buffer(outlink, n_out);
yading@10:     int ret;
yading@10: 
yading@10:     if(!outsamplesref)
yading@10:         return AVERROR(ENOMEM);
yading@10: 
yading@10:     av_frame_copy_props(outsamplesref, insamplesref);
yading@10:     outsamplesref->format                = outlink->format;
yading@10:     av_frame_set_channels(outsamplesref, outlink->channels);
yading@10:     outsamplesref->channel_layout        = outlink->channel_layout;
yading@10:     outsamplesref->sample_rate           = outlink->sample_rate;
yading@10: 
yading@10:     if(insamplesref->pts != AV_NOPTS_VALUE) {
yading@10:         int64_t inpts = av_rescale(insamplesref->pts, inlink->time_base.num * (int64_t)outlink->sample_rate * inlink->sample_rate, inlink->time_base.den);
yading@10:         int64_t outpts= swr_next_pts(aresample->swr, inpts);
yading@10:         aresample->next_pts =
yading@10:         outsamplesref->pts  = ROUNDED_DIV(outpts, inlink->sample_rate);
yading@10:     } else {
yading@10:         outsamplesref->pts  = AV_NOPTS_VALUE;
yading@10:     }
yading@10:     n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out,
yading@10:                                  (void *)insamplesref->extended_data, n_in);
yading@10:     if (n_out <= 0) {
yading@10:         av_frame_free(&outsamplesref);
yading@10:         av_frame_free(&insamplesref);
yading@10:         return 0;
yading@10:     }
yading@10: 
yading@10:     outsamplesref->nb_samples  = n_out;
yading@10: 
yading@10:     ret = ff_filter_frame(outlink, outsamplesref);
yading@10:     aresample->req_fullfilled= 1;
yading@10:     av_frame_free(&insamplesref);
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static int request_frame(AVFilterLink *outlink)
yading@10: {
yading@10:     AVFilterContext *ctx = outlink->src;
yading@10:     AResampleContext *aresample = ctx->priv;
yading@10:     AVFilterLink *const inlink = outlink->src->inputs[0];
yading@10:     int ret;
yading@10: 
yading@10:     aresample->req_fullfilled = 0;
yading@10:     do{
yading@10:         ret = ff_request_frame(ctx->inputs[0]);
yading@10:     }while(!aresample->req_fullfilled && ret>=0);
yading@10: 
yading@10:     if (ret == AVERROR_EOF) {
yading@10:         AVFrame *outsamplesref;
yading@10:         int n_out = 4096;
yading@10: 
yading@10:         outsamplesref = ff_get_audio_buffer(outlink, n_out);
yading@10:         if (!outsamplesref)
yading@10:             return AVERROR(ENOMEM);
yading@10:         n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out, 0, 0);
yading@10:         if (n_out <= 0) {
yading@10:             av_frame_free(&outsamplesref);
yading@10:             return (n_out == 0) ? AVERROR_EOF : n_out;
yading@10:         }
yading@10: 
yading@10:         outsamplesref->sample_rate = outlink->sample_rate;
yading@10:         outsamplesref->nb_samples  = n_out;
yading@10: #if 0
yading@10:         outsamplesref->pts = aresample->next_pts;
yading@10:         if(aresample->next_pts != AV_NOPTS_VALUE)
yading@10:             aresample->next_pts += av_rescale_q(n_out, (AVRational){1 ,outlink->sample_rate}, outlink->time_base);
yading@10: #else
yading@10:         outsamplesref->pts = swr_next_pts(aresample->swr, INT64_MIN);
yading@10:         outsamplesref->pts = ROUNDED_DIV(outsamplesref->pts, inlink->sample_rate);
yading@10: #endif
yading@10: 
yading@10:         return ff_filter_frame(outlink, outsamplesref);
yading@10:     }
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static const AVClass *resample_child_class_next(const AVClass *prev)
yading@10: {
yading@10:     return prev ? NULL : swr_get_class();
yading@10: }
yading@10: 
yading@10: static void *resample_child_next(void *obj, void *prev)
yading@10: {
yading@10:     AResampleContext *s = obj;
yading@10:     return prev ? NULL : s->swr;
yading@10: }
yading@10: 
yading@10: #define OFFSET(x) offsetof(AResampleContext, x)
yading@10: #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
yading@10: 
yading@10: static const AVOption options[] = {
yading@10:     {"sample_rate", NULL, OFFSET(sample_rate_arg), AV_OPT_TYPE_INT, {.i64=0},  0,        INT_MAX, FLAGS },
yading@10:     {NULL}
yading@10: };
yading@10: 
yading@10: static const AVClass aresample_class = {
yading@10:     .class_name       = "aresample",
yading@10:     .item_name        = av_default_item_name,
yading@10:     .option           = options,
yading@10:     .version          = LIBAVUTIL_VERSION_INT,
yading@10:     .child_class_next = resample_child_class_next,
yading@10:     .child_next       = resample_child_next,
yading@10: };
yading@10: 
yading@10: static const AVFilterPad aresample_inputs[] = {
yading@10:     {
yading@10:         .name         = "default",
yading@10:         .type         = AVMEDIA_TYPE_AUDIO,
yading@10:         .filter_frame = filter_frame,
yading@10:     },
yading@10:     { NULL },
yading@10: };
yading@10: 
yading@10: static const AVFilterPad aresample_outputs[] = {
yading@10:     {
yading@10:         .name          = "default",
yading@10:         .config_props  = config_output,
yading@10:         .request_frame = request_frame,
yading@10:         .type          = AVMEDIA_TYPE_AUDIO,
yading@10:     },
yading@10:     { NULL },
yading@10: };
yading@10: 
yading@10: AVFilter avfilter_af_aresample = {
yading@10:     .name          = "aresample",
yading@10:     .description   = NULL_IF_CONFIG_SMALL("Resample audio data."),
yading@10:     .init_dict     = init_dict,
yading@10:     .uninit        = uninit,
yading@10:     .query_formats = query_formats,
yading@10:     .priv_size     = sizeof(AResampleContext),
yading@10:     .priv_class    = &aresample_class,
yading@10:     .inputs        = aresample_inputs,
yading@10:     .outputs       = aresample_outputs,
yading@10: };