| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * Copyright 2010 S.N. Hemanth Meenakshisundaram <smeenaks ucsd edu> | ||
| 3 | * Copyright 2010 Stefano Sabatini <stefano.sabatini-lala poste it> | ||
| 4 | * | ||
| 5 | * This file is part of FFmpeg. | ||
| 6 | * | ||
| 7 | * FFmpeg is free software; you can redistribute it and/or | ||
| 8 | * modify it under the terms of the GNU Lesser General Public | ||
| 9 | * License as published by the Free Software Foundation; either | ||
| 10 | * version 2.1 of the License, or (at your option) any later version. | ||
| 11 | * | ||
| 12 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 15 | * Lesser General Public License for more details. | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU Lesser General Public | ||
| 18 | * License along with FFmpeg; if not, write to the Free Software | ||
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 20 | */ | ||
| 21 | |||
| 22 | /** | ||
| 23 | * @file | ||
| 24 | * null audio source | ||
| 25 | */ | ||
| 26 | |||
| 27 | #include <inttypes.h> | ||
| 28 | #include <stdio.h> | ||
| 29 | |||
| 30 | #include "libavutil/channel_layout.h" | ||
| 31 | #include "libavutil/internal.h" | ||
| 32 | #include "libavutil/opt.h" | ||
| 33 | #include "audio.h" | ||
| 34 | #include "avfilter.h" | ||
| 35 | #include "filters.h" | ||
| 36 | #include "formats.h" | ||
| 37 | #include "internal.h" | ||
| 38 | |||
| 39 | typedef struct ANullContext { | ||
| 40 | const AVClass *class; | ||
| 41 | AVChannelLayout ch_layout; | ||
| 42 | int sample_rate; | ||
| 43 | int64_t duration; | ||
| 44 | int nb_samples; ///< number of samples per requested frame | ||
| 45 | int64_t pts; | ||
| 46 | } ANullContext; | ||
| 47 | |||
| 48 | #define OFFSET(x) offsetof(ANullContext, x) | ||
| 49 | #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM | ||
| 50 | |||
| 51 | static const AVOption anullsrc_options[]= { | ||
| 52 | { "channel_layout", "set channel_layout", OFFSET(ch_layout), AV_OPT_TYPE_CHLAYOUT, {.str = "stereo"}, 0, 0, FLAGS }, | ||
| 53 | { "cl", "set channel_layout", OFFSET(ch_layout), AV_OPT_TYPE_CHLAYOUT, {.str = "stereo"}, 0, 0, FLAGS }, | ||
| 54 | { "sample_rate", "set sample rate", OFFSET(sample_rate) , AV_OPT_TYPE_INT, {.i64 = 44100}, 1, INT_MAX, FLAGS }, | ||
| 55 | { "r", "set sample rate", OFFSET(sample_rate) , AV_OPT_TYPE_INT, {.i64 = 44100}, 1, INT_MAX, FLAGS }, | ||
| 56 | { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, UINT16_MAX, FLAGS }, | ||
| 57 | { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, UINT16_MAX, FLAGS }, | ||
| 58 | { "duration", "set the audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS }, | ||
| 59 | { "d", "set the audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS }, | ||
| 60 | { NULL } | ||
| 61 | }; | ||
| 62 | |||
| 63 | AVFILTER_DEFINE_CLASS(anullsrc); | ||
| 64 | |||
| 65 | ✗ | static int query_formats(AVFilterContext *ctx) | |
| 66 | { | ||
| 67 | ✗ | ANullContext *null = ctx->priv; | |
| 68 | ✗ | const AVChannelLayout chlayouts[] = { null->ch_layout, { 0 } }; | |
| 69 | ✗ | int sample_rates[] = { null->sample_rate, -1 }; | |
| 70 | int ret; | ||
| 71 | |||
| 72 | ✗ | if ((ret = ff_set_common_formats (ctx, ff_all_formats (AVMEDIA_TYPE_AUDIO))) < 0 || | |
| 73 | ✗ | (ret = ff_set_common_samplerates_from_list(ctx, sample_rates)) < 0) | |
| 74 | ✗ | return ret; | |
| 75 | |||
| 76 | ✗ | return ff_set_common_channel_layouts_from_list(ctx, chlayouts); | |
| 77 | } | ||
| 78 | |||
| 79 | ✗ | static av_cold int config_props(AVFilterLink *outlink) | |
| 80 | { | ||
| 81 | ✗ | ANullContext *null = outlink->src->priv; | |
| 82 | |||
| 83 | ✗ | if (null->duration >= 0) | |
| 84 | ✗ | null->duration = av_rescale(null->duration, null->sample_rate, AV_TIME_BASE); | |
| 85 | |||
| 86 | ✗ | return 0; | |
| 87 | } | ||
| 88 | |||
| 89 | ✗ | static int activate(AVFilterContext *ctx) | |
| 90 | { | ||
| 91 | ✗ | ANullContext *null = ctx->priv; | |
| 92 | ✗ | AVFilterLink *outlink = ctx->outputs[0]; | |
| 93 | |||
| 94 | ✗ | if (null->duration >= 0 && null->pts >= null->duration) { | |
| 95 | ✗ | ff_outlink_set_status(outlink, AVERROR_EOF, null->pts); | |
| 96 | ✗ | return 0; | |
| 97 | } | ||
| 98 | |||
| 99 | ✗ | if (ff_outlink_frame_wanted(outlink)) { | |
| 100 | ✗ | AVFrame *samplesref = ff_get_audio_buffer(outlink, null->duration >= 0 ? FFMIN(null->nb_samples, null->duration - null->pts) : null->nb_samples); | |
| 101 | |||
| 102 | ✗ | if (!samplesref) | |
| 103 | ✗ | return AVERROR(ENOMEM); | |
| 104 | |||
| 105 | ✗ | samplesref->pts = null->pts; | |
| 106 | ✗ | null->pts += samplesref->nb_samples; | |
| 107 | |||
| 108 | ✗ | return ff_filter_frame(outlink, samplesref); | |
| 109 | } | ||
| 110 | |||
| 111 | ✗ | return FFERROR_NOT_READY; | |
| 112 | } | ||
| 113 | |||
| 114 | static const AVFilterPad avfilter_asrc_anullsrc_outputs[] = { | ||
| 115 | { | ||
| 116 | .name = "default", | ||
| 117 | .type = AVMEDIA_TYPE_AUDIO, | ||
| 118 | .config_props = config_props, | ||
| 119 | }, | ||
| 120 | }; | ||
| 121 | |||
| 122 | const AVFilter ff_asrc_anullsrc = { | ||
| 123 | .name = "anullsrc", | ||
| 124 | .description = NULL_IF_CONFIG_SMALL("Null audio source, return empty audio frames."), | ||
| 125 | .priv_size = sizeof(ANullContext), | ||
| 126 | .inputs = NULL, | ||
| 127 | FILTER_OUTPUTS(avfilter_asrc_anullsrc_outputs), | ||
| 128 | FILTER_QUERY_FUNC(query_formats), | ||
| 129 | .activate = activate, | ||
| 130 | .priv_class = &anullsrc_class, | ||
| 131 | }; | ||
| 132 |