h264_metadata: Add option to delete filler data
[libav.git] / libavfilter / af_channelsplit.c
1 /*
2 * This file is part of Libav.
3 *
4 * Libav is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * Libav is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with Libav; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19 /**
20 * @file
21 * Channel split filter
22 *
23 * Split an audio stream into per-channel streams.
24 */
25
26 #include "libavutil/attributes.h"
27 #include "libavutil/channel_layout.h"
28 #include "libavutil/internal.h"
29 #include "libavutil/opt.h"
30
31 #include "audio.h"
32 #include "avfilter.h"
33 #include "formats.h"
34 #include "internal.h"
35
36 typedef struct ChannelSplitContext {
37 const AVClass *class;
38
39 uint64_t channel_layout;
40 char *channel_layout_str;
41 } ChannelSplitContext;
42
43 #define OFFSET(x) offsetof(ChannelSplitContext, x)
44 #define A AV_OPT_FLAG_AUDIO_PARAM
45 static const AVOption options[] = {
46 { "channel_layout", "Input channel layout.", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, { .str = "stereo" }, .flags = A },
47 { NULL },
48 };
49
50 static const AVClass channelsplit_class = {
51 .class_name = "channelsplit filter",
52 .item_name = av_default_item_name,
53 .option = options,
54 .version = LIBAVUTIL_VERSION_INT,
55 };
56
57 static av_cold int init(AVFilterContext *ctx)
58 {
59 ChannelSplitContext *s = ctx->priv;
60 int nb_channels;
61 int ret = 0, i;
62
63 if (!(s->channel_layout = av_get_channel_layout(s->channel_layout_str))) {
64 av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
65 s->channel_layout_str);
66 ret = AVERROR(EINVAL);
67 goto fail;
68 }
69
70 nb_channels = av_get_channel_layout_nb_channels(s->channel_layout);
71 for (i = 0; i < nb_channels; i++) {
72 uint64_t channel = av_channel_layout_extract_channel(s->channel_layout, i);
73 AVFilterPad pad = { 0 };
74
75 pad.type = AVMEDIA_TYPE_AUDIO;
76 pad.name = av_get_channel_name(channel);
77
78 ff_insert_outpad(ctx, i, &pad);
79 }
80
81 fail:
82 return ret;
83 }
84
85 static int query_formats(AVFilterContext *ctx)
86 {
87 ChannelSplitContext *s = ctx->priv;
88 AVFilterChannelLayouts *in_layouts = NULL;
89 int i;
90
91 ff_set_common_formats (ctx, ff_planar_sample_fmts());
92 ff_set_common_samplerates(ctx, ff_all_samplerates());
93
94 ff_add_channel_layout(&in_layouts, s->channel_layout);
95 ff_channel_layouts_ref(in_layouts, &ctx->inputs[0]->out_channel_layouts);
96
97 for (i = 0; i < ctx->nb_outputs; i++) {
98 AVFilterChannelLayouts *out_layouts = NULL;
99 uint64_t channel = av_channel_layout_extract_channel(s->channel_layout, i);
100
101 ff_add_channel_layout(&out_layouts, channel);
102 ff_channel_layouts_ref(out_layouts, &ctx->outputs[i]->in_channel_layouts);
103 }
104
105 return 0;
106 }
107
108 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
109 {
110 AVFilterContext *ctx = inlink->dst;
111 int i, ret = 0;
112
113 for (i = 0; i < ctx->nb_outputs; i++) {
114 AVFrame *buf_out = av_frame_clone(buf);
115
116 if (!buf_out) {
117 ret = AVERROR(ENOMEM);
118 break;
119 }
120
121 buf_out->data[0] = buf_out->extended_data[0] = buf_out->extended_data[i];
122 buf_out->channel_layout =
123 av_channel_layout_extract_channel(buf->channel_layout, i);
124
125 ret = ff_filter_frame(ctx->outputs[i], buf_out);
126 if (ret < 0)
127 break;
128 }
129 av_frame_free(&buf);
130 return ret;
131 }
132
133 static const AVFilterPad avfilter_af_channelsplit_inputs[] = {
134 {
135 .name = "default",
136 .type = AVMEDIA_TYPE_AUDIO,
137 .filter_frame = filter_frame,
138 },
139 { NULL }
140 };
141
142 AVFilter ff_af_channelsplit = {
143 .name = "channelsplit",
144 .description = NULL_IF_CONFIG_SMALL("Split audio into per-channel streams"),
145 .priv_size = sizeof(ChannelSplitContext),
146 .priv_class = &channelsplit_class,
147
148 .init = init,
149 .query_formats = query_formats,
150
151 .inputs = avfilter_af_channelsplit_inputs,
152 .outputs = NULL,
153
154 .flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS,
155 };