Commit | Line | Data |
---|---|---|
2ba45a60 DM |
1 | /* |
2 | * Copyright (c) 2012 Michael Niedermayer | |
3 | * | |
4 | * This file is part of FFmpeg. | |
5 | * | |
6 | * FFmpeg is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU Lesser General Public | |
8 | * License as published by the Free Software Foundation; either | |
9 | * version 2.1 of the License, or (at your option) any later version. | |
10 | * | |
11 | * FFmpeg is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | * Lesser General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU Lesser General Public | |
17 | * License along with FFmpeg; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | */ | |
20 | ||
21 | /** | |
22 | * @file | |
23 | * audio pad filter. | |
24 | * | |
25 | * Based on af_aresample.c | |
26 | */ | |
27 | ||
28 | #include "libavutil/avstring.h" | |
29 | #include "libavutil/channel_layout.h" | |
30 | #include "libavutil/opt.h" | |
31 | #include "libavutil/samplefmt.h" | |
32 | #include "libavutil/avassert.h" | |
33 | #include "avfilter.h" | |
34 | #include "audio.h" | |
35 | #include "internal.h" | |
36 | ||
37 | typedef struct { | |
38 | const AVClass *class; | |
39 | int64_t next_pts; | |
40 | ||
41 | int packet_size; | |
42 | int64_t pad_len, pad_len_left; | |
43 | int64_t whole_len, whole_len_left; | |
44 | } APadContext; | |
45 | ||
46 | #define OFFSET(x) offsetof(APadContext, x) | |
47 | #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM | |
48 | ||
49 | static const AVOption apad_options[] = { | |
50 | { "packet_size", "set silence packet size", OFFSET(packet_size), AV_OPT_TYPE_INT, { .i64 = 4096 }, 0, INT_MAX, A }, | |
51 | { "pad_len", "set number of samples of silence to add", OFFSET(pad_len), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, A }, | |
52 | { "whole_len", "set minimum target number of samples in the audio stream", OFFSET(whole_len), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, A }, | |
53 | { NULL } | |
54 | }; | |
55 | ||
56 | AVFILTER_DEFINE_CLASS(apad); | |
57 | ||
58 | static av_cold int init(AVFilterContext *ctx) | |
59 | { | |
60 | APadContext *apad = ctx->priv; | |
61 | ||
62 | apad->next_pts = AV_NOPTS_VALUE; | |
63 | if (apad->whole_len >= 0 && apad->pad_len >= 0) { | |
64 | av_log(ctx, AV_LOG_ERROR, "Both whole and pad length are set, this is not possible\n"); | |
65 | return AVERROR(EINVAL); | |
66 | } | |
67 | apad->pad_len_left = apad->pad_len; | |
68 | apad->whole_len_left = apad->whole_len; | |
69 | ||
70 | return 0; | |
71 | } | |
72 | ||
73 | static int filter_frame(AVFilterLink *inlink, AVFrame *frame) | |
74 | { | |
75 | AVFilterContext *ctx = inlink->dst; | |
76 | APadContext *apad = ctx->priv; | |
77 | ||
78 | if (apad->whole_len >= 0) { | |
79 | apad->whole_len_left = FFMAX(apad->whole_len_left - frame->nb_samples, 0); | |
80 | av_log(ctx, AV_LOG_DEBUG, | |
81 | "n_out:%d whole_len_left:%"PRId64"\n", frame->nb_samples, apad->whole_len_left); | |
82 | } | |
83 | ||
84 | apad->next_pts = frame->pts + av_rescale_q(frame->nb_samples, (AVRational){1, inlink->sample_rate}, inlink->time_base); | |
85 | return ff_filter_frame(ctx->outputs[0], frame); | |
86 | } | |
87 | ||
88 | static int request_frame(AVFilterLink *outlink) | |
89 | { | |
90 | AVFilterContext *ctx = outlink->src; | |
91 | APadContext *apad = ctx->priv; | |
92 | int ret; | |
93 | ||
94 | ret = ff_request_frame(ctx->inputs[0]); | |
95 | ||
96 | if (ret == AVERROR_EOF && !ctx->is_disabled) { | |
97 | int n_out = apad->packet_size; | |
98 | AVFrame *outsamplesref; | |
99 | ||
100 | if (apad->whole_len >= 0 && apad->pad_len < 0) { | |
101 | apad->pad_len = apad->pad_len_left = apad->whole_len_left; | |
102 | } | |
103 | if (apad->pad_len >=0 || apad->whole_len >= 0) { | |
104 | n_out = FFMIN(n_out, apad->pad_len_left); | |
105 | apad->pad_len_left -= n_out; | |
106 | av_log(ctx, AV_LOG_DEBUG, | |
107 | "padding n_out:%d pad_len_left:%"PRId64"\n", n_out, apad->pad_len_left); | |
108 | } | |
109 | ||
110 | if (!n_out) | |
111 | return AVERROR_EOF; | |
112 | ||
113 | outsamplesref = ff_get_audio_buffer(outlink, n_out); | |
114 | if (!outsamplesref) | |
115 | return AVERROR(ENOMEM); | |
116 | ||
117 | av_assert0(outsamplesref->sample_rate == outlink->sample_rate); | |
118 | av_assert0(outsamplesref->nb_samples == n_out); | |
119 | ||
120 | av_samples_set_silence(outsamplesref->extended_data, 0, | |
121 | n_out, | |
122 | av_frame_get_channels(outsamplesref), | |
123 | outsamplesref->format); | |
124 | ||
125 | outsamplesref->pts = apad->next_pts; | |
126 | if (apad->next_pts != AV_NOPTS_VALUE) | |
127 | apad->next_pts += av_rescale_q(n_out, (AVRational){1, outlink->sample_rate}, outlink->time_base); | |
128 | ||
129 | return ff_filter_frame(outlink, outsamplesref); | |
130 | } | |
131 | return ret; | |
132 | } | |
133 | ||
134 | static const AVFilterPad apad_inputs[] = { | |
135 | { | |
136 | .name = "default", | |
137 | .type = AVMEDIA_TYPE_AUDIO, | |
138 | .filter_frame = filter_frame, | |
139 | }, | |
140 | { NULL } | |
141 | }; | |
142 | ||
143 | static const AVFilterPad apad_outputs[] = { | |
144 | { | |
145 | .name = "default", | |
146 | .request_frame = request_frame, | |
147 | .type = AVMEDIA_TYPE_AUDIO, | |
148 | }, | |
149 | { NULL } | |
150 | }; | |
151 | ||
152 | AVFilter ff_af_apad = { | |
153 | .name = "apad", | |
154 | .description = NULL_IF_CONFIG_SMALL("Pad audio with silence."), | |
155 | .init = init, | |
156 | .priv_size = sizeof(APadContext), | |
157 | .inputs = apad_inputs, | |
158 | .outputs = apad_outputs, | |
159 | .priv_class = &apad_class, | |
160 | .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL, | |
161 | }; |