GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/af_channelsplit.c Lines: 46 62 74.2 %
Date: 2020-10-23 17:01:47 Branches: 18 34 52.9 %

Line Branch Exec Source
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/*
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Channel split filter
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 *
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 * Split an audio stream into per-channel streams.
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 */
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#include "libavutil/attributes.h"
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#include "libavutil/channel_layout.h"
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#include "libavutil/internal.h"
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#include "libavutil/opt.h"
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#include "audio.h"
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#include "avfilter.h"
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#include "formats.h"
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#include "internal.h"
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typedef struct ChannelSplitContext {
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    const AVClass *class;
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    uint64_t channel_layout;
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    char    *channel_layout_str;
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    char    *channels_str;
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    int      map[64];
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} ChannelSplitContext;
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#define OFFSET(x) offsetof(ChannelSplitContext, x)
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#define A AV_OPT_FLAG_AUDIO_PARAM
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#define F AV_OPT_FLAG_FILTERING_PARAM
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static const AVOption channelsplit_options[] = {
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    { "channel_layout", "Input channel layout.", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, { .str = "stereo" }, .flags = A|F },
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    { "channels",        "Channels to extract.", OFFSET(channels_str),       AV_OPT_TYPE_STRING, { .str = "all" },    .flags = A|F },
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    { NULL }
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};
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AVFILTER_DEFINE_CLASS(channelsplit);
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static av_cold int init(AVFilterContext *ctx)
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{
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    ChannelSplitContext *s = ctx->priv;
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    uint64_t channel_layout;
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    int nb_channels;
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    int all = 0, ret = 0, i;
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    if (!(s->channel_layout = av_get_channel_layout(s->channel_layout_str))) {
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        av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
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               s->channel_layout_str);
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        ret = AVERROR(EINVAL);
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        goto fail;
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    }
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    if (!strcmp(s->channels_str, "all")) {
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        nb_channels = av_get_channel_layout_nb_channels(s->channel_layout);
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        channel_layout = s->channel_layout;
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        all = 1;
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    } else {
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        if ((ret = av_get_extended_channel_layout(s->channels_str, &channel_layout, &nb_channels)) < 0)
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            return ret;
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    }
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    for (i = 0; i < nb_channels; i++) {
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        uint64_t channel = av_channel_layout_extract_channel(channel_layout, i);
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        AVFilterPad pad  = { 0 };
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        pad.type = AVMEDIA_TYPE_AUDIO;
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        pad.name = av_get_channel_name(channel);
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        if (all) {
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            s->map[i] = i;
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        } else {
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            if ((ret = av_get_channel_layout_channel_index(s->channel_layout, channel)) < 0) {
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                av_log(ctx, AV_LOG_ERROR, "Channel name '%s' not present in channel layout '%s'.\n",
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                       av_get_channel_name(channel), s->channel_layout_str);
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                return ret;
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            }
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            s->map[i] = ret;
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        }
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        if ((ret = ff_insert_outpad(ctx, i, &pad)) < 0) {
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            return ret;
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        }
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    }
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fail:
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    return ret;
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}
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static int query_formats(AVFilterContext *ctx)
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{
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    ChannelSplitContext *s = ctx->priv;
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    AVFilterChannelLayouts *in_layouts = NULL;
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    int i, ret;
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    if ((ret = ff_set_common_formats(ctx, ff_planar_sample_fmts())) < 0 ||
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1
        (ret = ff_set_common_samplerates(ctx, ff_all_samplerates())) < 0)
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        return ret;
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    if ((ret = ff_add_channel_layout(&in_layouts, s->channel_layout)) < 0 ||
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        (ret = ff_channel_layouts_ref(in_layouts, &ctx->inputs[0]->outcfg.channel_layouts)) < 0)
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        return ret;
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    for (i = 0; i < ctx->nb_outputs; i++) {
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        AVFilterChannelLayouts *out_layouts = NULL;
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        uint64_t channel = av_channel_layout_extract_channel(s->channel_layout, s->map[i]);
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        if ((ret = ff_add_channel_layout(&out_layouts, channel)) < 0 ||
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            (ret = ff_channel_layouts_ref(out_layouts, &ctx->outputs[i]->incfg.channel_layouts)) < 0)
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            return ret;
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    }
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    return 0;
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}
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static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
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{
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    AVFilterContext *ctx = inlink->dst;
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    ChannelSplitContext *s = ctx->priv;
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    int i, ret = 0;
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    for (i = 0; i < ctx->nb_outputs; i++) {
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        AVFrame *buf_out = av_frame_clone(buf);
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        if (!buf_out) {
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            ret = AVERROR(ENOMEM);
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            break;
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        }
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        buf_out->data[0] = buf_out->extended_data[0] = buf_out->extended_data[s->map[i]];
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        buf_out->channel_layout =
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            av_channel_layout_extract_channel(buf->channel_layout, s->map[i]);
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        buf_out->channels = 1;
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        ret = ff_filter_frame(ctx->outputs[i], buf_out);
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        if (ret < 0)
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            break;
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    }
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    av_frame_free(&buf);
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    return ret;
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}
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static const AVFilterPad avfilter_af_channelsplit_inputs[] = {
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    {
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        .name         = "default",
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        .type         = AVMEDIA_TYPE_AUDIO,
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        .filter_frame = filter_frame,
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    },
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    { NULL }
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};
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AVFilter ff_af_channelsplit = {
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    .name           = "channelsplit",
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    .description    = NULL_IF_CONFIG_SMALL("Split audio into per-channel streams."),
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    .priv_size      = sizeof(ChannelSplitContext),
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    .priv_class     = &channelsplit_class,
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    .init           = init,
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    .query_formats  = query_formats,
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    .inputs         = avfilter_af_channelsplit_inputs,
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    .outputs        = NULL,
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    .flags          = AVFILTER_FLAG_DYNAMIC_OUTPUTS,
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};