| /* |
| * |
| * This file is part of Libav. |
| * |
| * Libav is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * Libav is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with Libav; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * sample format and channel layout conversion audio filter |
| */ |
| |
| #include "libavutil/avassert.h" |
| #include "libavutil/avstring.h" |
| #include "libavutil/common.h" |
| #include "libavutil/mathematics.h" |
| #include "libavutil/opt.h" |
| |
| #include "libavresample/avresample.h" |
| |
| #include "audio.h" |
| #include "avfilter.h" |
| #include "formats.h" |
| #include "internal.h" |
| |
| typedef struct ResampleContext { |
| AVAudioResampleContext *avr; |
| |
| int64_t next_pts; |
| |
| /* set by filter_frame() to signal an output frame to request_frame() */ |
| int got_output; |
| } ResampleContext; |
| |
| static av_cold void uninit(AVFilterContext *ctx) |
| { |
| ResampleContext *s = ctx->priv; |
| |
| if (s->avr) { |
| avresample_close(s->avr); |
| avresample_free(&s->avr); |
| } |
| } |
| |
| static int query_formats(AVFilterContext *ctx) |
| { |
| AVFilterLink *inlink = ctx->inputs[0]; |
| AVFilterLink *outlink = ctx->outputs[0]; |
| |
| AVFilterFormats *in_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO); |
| AVFilterFormats *out_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO); |
| AVFilterFormats *in_samplerates = ff_all_samplerates(); |
| AVFilterFormats *out_samplerates = ff_all_samplerates(); |
| AVFilterChannelLayouts *in_layouts = ff_all_channel_layouts(); |
| AVFilterChannelLayouts *out_layouts = ff_all_channel_layouts(); |
| |
| ff_formats_ref(in_formats, &inlink->out_formats); |
| ff_formats_ref(out_formats, &outlink->in_formats); |
| |
| ff_formats_ref(in_samplerates, &inlink->out_samplerates); |
| ff_formats_ref(out_samplerates, &outlink->in_samplerates); |
| |
| ff_channel_layouts_ref(in_layouts, &inlink->out_channel_layouts); |
| ff_channel_layouts_ref(out_layouts, &outlink->in_channel_layouts); |
| |
| return 0; |
| } |
| |
| static int config_output(AVFilterLink *outlink) |
| { |
| AVFilterContext *ctx = outlink->src; |
| AVFilterLink *inlink = ctx->inputs[0]; |
| ResampleContext *s = ctx->priv; |
| char buf1[64], buf2[64]; |
| int ret; |
| |
| if (s->avr) { |
| avresample_close(s->avr); |
| avresample_free(&s->avr); |
| } |
| |
| if (inlink->channel_layout == outlink->channel_layout && |
| inlink->sample_rate == outlink->sample_rate && |
| (inlink->format == outlink->format || |
| (av_get_channel_layout_nb_channels(inlink->channel_layout) == 1 && |
| av_get_channel_layout_nb_channels(outlink->channel_layout) == 1 && |
| av_get_planar_sample_fmt(inlink->format) == |
| av_get_planar_sample_fmt(outlink->format)))) |
| return 0; |
| |
| if (!(s->avr = avresample_alloc_context())) |
| return AVERROR(ENOMEM); |
| |
| av_opt_set_int(s->avr, "in_channel_layout", inlink ->channel_layout, 0); |
| av_opt_set_int(s->avr, "out_channel_layout", outlink->channel_layout, 0); |
| av_opt_set_int(s->avr, "in_sample_fmt", inlink ->format, 0); |
| av_opt_set_int(s->avr, "out_sample_fmt", outlink->format, 0); |
| av_opt_set_int(s->avr, "in_sample_rate", inlink ->sample_rate, 0); |
| av_opt_set_int(s->avr, "out_sample_rate", outlink->sample_rate, 0); |
| |
| if ((ret = avresample_open(s->avr)) < 0) |
| return ret; |
| |
| outlink->time_base = (AVRational){ 1, outlink->sample_rate }; |
| s->next_pts = AV_NOPTS_VALUE; |
| |
| av_get_channel_layout_string(buf1, sizeof(buf1), |
| -1, inlink ->channel_layout); |
| av_get_channel_layout_string(buf2, sizeof(buf2), |
| -1, outlink->channel_layout); |
| av_log(ctx, AV_LOG_VERBOSE, |
| "fmt:%s srate:%d cl:%s -> fmt:%s srate:%d cl:%s\n", |
| av_get_sample_fmt_name(inlink ->format), inlink ->sample_rate, buf1, |
| av_get_sample_fmt_name(outlink->format), outlink->sample_rate, buf2); |
| |
| return 0; |
| } |
| |
| static int request_frame(AVFilterLink *outlink) |
| { |
| AVFilterContext *ctx = outlink->src; |
| ResampleContext *s = ctx->priv; |
| int ret = 0; |
| |
| s->got_output = 0; |
| while (ret >= 0 && !s->got_output) |
| ret = ff_request_frame(ctx->inputs[0]); |
| |
| /* flush the lavr delay buffer */ |
| if (ret == AVERROR_EOF && s->avr) { |
| AVFilterBufferRef *buf; |
| int nb_samples = av_rescale_rnd(avresample_get_delay(s->avr), |
| outlink->sample_rate, |
| ctx->inputs[0]->sample_rate, |
| AV_ROUND_UP); |
| |
| if (!nb_samples) |
| return ret; |
| |
| buf = ff_get_audio_buffer(outlink, AV_PERM_WRITE, nb_samples); |
| if (!buf) |
| return AVERROR(ENOMEM); |
| |
| ret = avresample_convert(s->avr, buf->extended_data, |
| buf->linesize[0], nb_samples, |
| NULL, 0, 0); |
| if (ret <= 0) { |
| avfilter_unref_buffer(buf); |
| return (ret == 0) ? AVERROR_EOF : ret; |
| } |
| |
| buf->pts = s->next_pts; |
| return ff_filter_frame(outlink, buf); |
| } |
| return ret; |
| } |
| |
| static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *buf) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| ResampleContext *s = ctx->priv; |
| AVFilterLink *outlink = ctx->outputs[0]; |
| int ret; |
| |
| if (s->avr) { |
| AVFilterBufferRef *buf_out; |
| int delay, nb_samples; |
| |
| /* maximum possible samples lavr can output */ |
| delay = avresample_get_delay(s->avr); |
| nb_samples = av_rescale_rnd(buf->audio->nb_samples + delay, |
| outlink->sample_rate, inlink->sample_rate, |
| AV_ROUND_UP); |
| |
| buf_out = ff_get_audio_buffer(outlink, AV_PERM_WRITE, nb_samples); |
| if (!buf_out) { |
| ret = AVERROR(ENOMEM); |
| goto fail; |
| } |
| |
| ret = avresample_convert(s->avr, buf_out->extended_data, |
| buf_out->linesize[0], nb_samples, |
| buf->extended_data, buf->linesize[0], |
| buf->audio->nb_samples); |
| if (ret <= 0) { |
| avfilter_unref_buffer(buf_out); |
| if (ret < 0) |
| goto fail; |
| } |
| |
| av_assert0(!avresample_available(s->avr)); |
| |
| if (s->next_pts == AV_NOPTS_VALUE) { |
| if (buf->pts == AV_NOPTS_VALUE) { |
| av_log(ctx, AV_LOG_WARNING, "First timestamp is missing, " |
| "assuming 0.\n"); |
| s->next_pts = 0; |
| } else |
| s->next_pts = av_rescale_q(buf->pts, inlink->time_base, |
| outlink->time_base); |
| } |
| |
| if (ret > 0) { |
| buf_out->audio->nb_samples = ret; |
| if (buf->pts != AV_NOPTS_VALUE) { |
| buf_out->pts = av_rescale_q(buf->pts, inlink->time_base, |
| outlink->time_base) - |
| av_rescale(delay, outlink->sample_rate, |
| inlink->sample_rate); |
| } else |
| buf_out->pts = s->next_pts; |
| |
| s->next_pts = buf_out->pts + buf_out->audio->nb_samples; |
| |
| ret = ff_filter_frame(outlink, buf_out); |
| s->got_output = 1; |
| } |
| |
| fail: |
| avfilter_unref_buffer(buf); |
| } else { |
| buf->format = outlink->format; |
| ret = ff_filter_frame(outlink, buf); |
| s->got_output = 1; |
| } |
| |
| return ret; |
| } |
| |
| static const AVFilterPad avfilter_af_resample_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .filter_frame = filter_frame, |
| .min_perms = AV_PERM_READ |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad avfilter_af_resample_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .config_props = config_output, |
| .request_frame = request_frame |
| }, |
| { NULL } |
| }; |
| |
| AVFilter avfilter_af_resample = { |
| .name = "resample", |
| .description = NULL_IF_CONFIG_SMALL("Audio resampling and conversion."), |
| .priv_size = sizeof(ResampleContext), |
| |
| .uninit = uninit, |
| .query_formats = query_formats, |
| |
| .inputs = avfilter_af_resample_inputs, |
| .outputs = avfilter_af_resample_outputs, |
| }; |