yading@10: /*
yading@10:  *
yading@10:  * This file is part of Libav.
yading@10:  *
yading@10:  * Libav 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:  * Libav 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 Libav; 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:  * sample format and channel layout conversion audio filter
yading@10:  */
yading@10: 
yading@10: #include "libavutil/avassert.h"
yading@10: #include "libavutil/avstring.h"
yading@10: #include "libavutil/common.h"
yading@10: #include "libavutil/dict.h"
yading@10: #include "libavutil/mathematics.h"
yading@10: #include "libavutil/opt.h"
yading@10: 
yading@10: #include "libavresample/avresample.h"
yading@10: 
yading@10: #include "audio.h"
yading@10: #include "avfilter.h"
yading@10: #include "formats.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: typedef struct ResampleContext {
yading@10:     const AVClass *class;
yading@10:     AVAudioResampleContext *avr;
yading@10:     AVDictionary *options;
yading@10: 
yading@10:     int64_t next_pts;
yading@10: 
yading@10:     /* set by filter_frame() to signal an output frame to request_frame() */
yading@10:     int got_output;
yading@10: } ResampleContext;
yading@10: 
yading@10: static av_cold int init(AVFilterContext *ctx, AVDictionary **opts)
yading@10: {
yading@10:     ResampleContext *s = ctx->priv;
yading@10:     const AVClass *avr_class = avresample_get_class();
yading@10:     AVDictionaryEntry *e = NULL;
yading@10: 
yading@10:     while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
yading@10:         if (av_opt_find(&avr_class, e->key, NULL, 0,
yading@10:                         AV_OPT_SEARCH_FAKE_OBJ | AV_OPT_SEARCH_CHILDREN))
yading@10:             av_dict_set(&s->options, e->key, e->value, 0);
yading@10:     }
yading@10: 
yading@10:     e = NULL;
yading@10:     while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
yading@10:         av_dict_set(opts, e->key, NULL, 0);
yading@10: 
yading@10:     /* do not allow the user to override basic format options */
yading@10:     av_dict_set(&s->options,  "in_channel_layout", NULL, 0);
yading@10:     av_dict_set(&s->options, "out_channel_layout", NULL, 0);
yading@10:     av_dict_set(&s->options,  "in_sample_fmt",     NULL, 0);
yading@10:     av_dict_set(&s->options, "out_sample_fmt",     NULL, 0);
yading@10:     av_dict_set(&s->options,  "in_sample_rate",    NULL, 0);
yading@10:     av_dict_set(&s->options, "out_sample_rate",    NULL, 0);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold void uninit(AVFilterContext *ctx)
yading@10: {
yading@10:     ResampleContext *s = ctx->priv;
yading@10: 
yading@10:     if (s->avr) {
yading@10:         avresample_close(s->avr);
yading@10:         avresample_free(&s->avr);
yading@10:     }
yading@10:     av_dict_free(&s->options);
yading@10: }
yading@10: 
yading@10: static int query_formats(AVFilterContext *ctx)
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     = ff_all_formats(AVMEDIA_TYPE_AUDIO);
yading@10:     AVFilterFormats        *in_samplerates  = ff_all_samplerates();
yading@10:     AVFilterFormats        *out_samplerates = ff_all_samplerates();
yading@10:     AVFilterChannelLayouts *in_layouts      = ff_all_channel_layouts();
yading@10:     AVFilterChannelLayouts *out_layouts     = ff_all_channel_layouts();
yading@10: 
yading@10:     ff_formats_ref(in_formats,  &inlink->out_formats);
yading@10:     ff_formats_ref(out_formats, &outlink->in_formats);
yading@10: 
yading@10:     ff_formats_ref(in_samplerates,  &inlink->out_samplerates);
yading@10:     ff_formats_ref(out_samplerates, &outlink->in_samplerates);
yading@10: 
yading@10:     ff_channel_layouts_ref(in_layouts,  &inlink->out_channel_layouts);
yading@10:     ff_channel_layouts_ref(out_layouts, &outlink->in_channel_layouts);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int config_output(AVFilterLink *outlink)
yading@10: {
yading@10:     AVFilterContext *ctx = outlink->src;
yading@10:     AVFilterLink *inlink = ctx->inputs[0];
yading@10:     ResampleContext   *s = ctx->priv;
yading@10:     char buf1[64], buf2[64];
yading@10:     int ret;
yading@10: 
yading@10:     if (s->avr) {
yading@10:         avresample_close(s->avr);
yading@10:         avresample_free(&s->avr);
yading@10:     }
yading@10: 
yading@10:     if (inlink->channel_layout == outlink->channel_layout &&
yading@10:         inlink->sample_rate    == outlink->sample_rate    &&
yading@10:         (inlink->format        == outlink->format ||
yading@10:         (av_get_channel_layout_nb_channels(inlink->channel_layout)  == 1 &&
yading@10:          av_get_channel_layout_nb_channels(outlink->channel_layout) == 1 &&
yading@10:          av_get_planar_sample_fmt(inlink->format) ==
yading@10:          av_get_planar_sample_fmt(outlink->format))))
yading@10:         return 0;
yading@10: 
yading@10:     if (!(s->avr = avresample_alloc_context()))
yading@10:         return AVERROR(ENOMEM);
yading@10: 
yading@10:     if (s->options) {
yading@10:         AVDictionaryEntry *e = NULL;
yading@10:         while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
yading@10:             av_log(ctx, AV_LOG_VERBOSE, "lavr option: %s=%s\n", e->key, e->value);
yading@10: 
yading@10:         av_opt_set_dict(s->avr, &s->options);
yading@10:     }
yading@10: 
yading@10:     av_opt_set_int(s->avr,  "in_channel_layout", inlink ->channel_layout, 0);
yading@10:     av_opt_set_int(s->avr, "out_channel_layout", outlink->channel_layout, 0);
yading@10:     av_opt_set_int(s->avr,  "in_sample_fmt",     inlink ->format,         0);
yading@10:     av_opt_set_int(s->avr, "out_sample_fmt",     outlink->format,         0);
yading@10:     av_opt_set_int(s->avr,  "in_sample_rate",    inlink ->sample_rate,    0);
yading@10:     av_opt_set_int(s->avr, "out_sample_rate",    outlink->sample_rate,    0);
yading@10: 
yading@10:     if ((ret = avresample_open(s->avr)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     outlink->time_base = (AVRational){ 1, outlink->sample_rate };
yading@10:     s->next_pts        = AV_NOPTS_VALUE;
yading@10: 
yading@10:     av_get_channel_layout_string(buf1, sizeof(buf1),
yading@10:                                  -1, inlink ->channel_layout);
yading@10:     av_get_channel_layout_string(buf2, sizeof(buf2),
yading@10:                                  -1, outlink->channel_layout);
yading@10:     av_log(ctx, AV_LOG_VERBOSE,
yading@10:            "fmt:%s srate:%d cl:%s -> fmt:%s srate:%d cl:%s\n",
yading@10:            av_get_sample_fmt_name(inlink ->format), inlink ->sample_rate, buf1,
yading@10:            av_get_sample_fmt_name(outlink->format), outlink->sample_rate, buf2);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int request_frame(AVFilterLink *outlink)
yading@10: {
yading@10:     AVFilterContext *ctx = outlink->src;
yading@10:     ResampleContext   *s = ctx->priv;
yading@10:     int ret = 0;
yading@10: 
yading@10:     s->got_output = 0;
yading@10:     while (ret >= 0 && !s->got_output)
yading@10:         ret = ff_request_frame(ctx->inputs[0]);
yading@10: 
yading@10:     /* flush the lavr delay buffer */
yading@10:     if (ret == AVERROR_EOF && s->avr) {
yading@10:         AVFrame *frame;
yading@10:         int nb_samples = av_rescale_rnd(avresample_get_delay(s->avr),
yading@10:                                         outlink->sample_rate,
yading@10:                                         ctx->inputs[0]->sample_rate,
yading@10:                                         AV_ROUND_UP);
yading@10: 
yading@10:         if (!nb_samples)
yading@10:             return ret;
yading@10: 
yading@10:         frame = ff_get_audio_buffer(outlink, nb_samples);
yading@10:         if (!frame)
yading@10:             return AVERROR(ENOMEM);
yading@10: 
yading@10:         ret = avresample_convert(s->avr, frame->extended_data,
yading@10:                                  frame->linesize[0], nb_samples,
yading@10:                                  NULL, 0, 0);
yading@10:         if (ret <= 0) {
yading@10:             av_frame_free(&frame);
yading@10:             return (ret == 0) ? AVERROR_EOF : ret;
yading@10:         }
yading@10: 
yading@10:         frame->pts = s->next_pts;
yading@10:         return ff_filter_frame(outlink, frame);
yading@10:     }
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static int filter_frame(AVFilterLink *inlink, AVFrame *in)
yading@10: {
yading@10:     AVFilterContext  *ctx = inlink->dst;
yading@10:     ResampleContext    *s = ctx->priv;
yading@10:     AVFilterLink *outlink = ctx->outputs[0];
yading@10:     int ret;
yading@10: 
yading@10:     if (s->avr) {
yading@10:         AVFrame *out;
yading@10:         int delay, nb_samples;
yading@10: 
yading@10:         /* maximum possible samples lavr can output */
yading@10:         delay      = avresample_get_delay(s->avr);
yading@10:         nb_samples = av_rescale_rnd(in->nb_samples + delay,
yading@10:                                     outlink->sample_rate, inlink->sample_rate,
yading@10:                                     AV_ROUND_UP);
yading@10: 
yading@10:         out = ff_get_audio_buffer(outlink, nb_samples);
yading@10:         if (!out) {
yading@10:             ret = AVERROR(ENOMEM);
yading@10:             goto fail;
yading@10:         }
yading@10: 
yading@10:         ret = avresample_convert(s->avr, out->extended_data, out->linesize[0],
yading@10:                                  nb_samples, in->extended_data, in->linesize[0],
yading@10:                                  in->nb_samples);
yading@10:         if (ret <= 0) {
yading@10:             av_frame_free(&out);
yading@10:             if (ret < 0)
yading@10:                 goto fail;
yading@10:         }
yading@10: 
yading@10:         av_assert0(!avresample_available(s->avr));
yading@10: 
yading@10:         if (s->next_pts == AV_NOPTS_VALUE) {
yading@10:             if (in->pts == AV_NOPTS_VALUE) {
yading@10:                 av_log(ctx, AV_LOG_WARNING, "First timestamp is missing, "
yading@10:                        "assuming 0.\n");
yading@10:                 s->next_pts = 0;
yading@10:             } else
yading@10:                 s->next_pts = av_rescale_q(in->pts, inlink->time_base,
yading@10:                                            outlink->time_base);
yading@10:         }
yading@10: 
yading@10:         if (ret > 0) {
yading@10:             out->nb_samples = ret;
yading@10:             if (in->pts != AV_NOPTS_VALUE) {
yading@10:                 out->pts = av_rescale_q(in->pts, inlink->time_base,
yading@10:                                             outlink->time_base) -
yading@10:                                av_rescale(delay, outlink->sample_rate,
yading@10:                                           inlink->sample_rate);
yading@10:             } else
yading@10:                 out->pts = s->next_pts;
yading@10: 
yading@10:             s->next_pts = out->pts + out->nb_samples;
yading@10: 
yading@10:             ret = ff_filter_frame(outlink, out);
yading@10:             s->got_output = 1;
yading@10:         }
yading@10: 
yading@10: fail:
yading@10:         av_frame_free(&in);
yading@10:     } else {
yading@10:         in->format = outlink->format;
yading@10:         ret = ff_filter_frame(outlink, in);
yading@10:         s->got_output = 1;
yading@10:     }
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 : avresample_get_class();
yading@10: }
yading@10: 
yading@10: static void *resample_child_next(void *obj, void *prev)
yading@10: {
yading@10:     ResampleContext *s = obj;
yading@10:     return prev ? NULL : s->avr;
yading@10: }
yading@10: 
yading@10: static const AVClass resample_class = {
yading@10:     .class_name       = "resample",
yading@10:     .item_name        = av_default_item_name,
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 avfilter_af_resample_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 avfilter_af_resample_outputs[] = {
yading@10:     {
yading@10:         .name          = "default",
yading@10:         .type          = AVMEDIA_TYPE_AUDIO,
yading@10:         .config_props  = config_output,
yading@10:         .request_frame = request_frame
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: AVFilter avfilter_af_resample = {
yading@10:     .name          = "resample",
yading@10:     .description   = NULL_IF_CONFIG_SMALL("Audio resampling and conversion."),
yading@10:     .priv_size     = sizeof(ResampleContext),
yading@10:     .priv_class    = &resample_class,
yading@10: 
yading@10:     .init_dict      = init,
yading@10:     .uninit         = uninit,
yading@10:     .query_formats  = query_formats,
yading@10: 
yading@10:     .inputs    = avfilter_af_resample_inputs,
yading@10:     .outputs   = avfilter_af_resample_outputs,
yading@10: };