[deb_ffmpeg.git] / ffmpeg / libavfilter / af_channelmap.c

/*
 * Copyright (c) 2012 Google, Inc.
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * audio channel mapping filter
 */

#include <ctype.h>

#include "libavutil/avstring.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/samplefmt.h"

#include "audio.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"

struct ChannelMap {
    uint64_t in_channel;
    uint64_t out_channel;
    int in_channel_idx;
    int out_channel_idx;
};

enum MappingMode {
    MAP_NONE,
    MAP_ONE_INT,
    MAP_ONE_STR,
    MAP_PAIR_INT_INT,
    MAP_PAIR_INT_STR,
    MAP_PAIR_STR_INT,
    MAP_PAIR_STR_STR
};

#define MAX_CH 64
typedef struct ChannelMapContext {
    const AVClass *class;
    AVFilterChannelLayouts *channel_layouts;
    char *mapping_str;
    char *channel_layout_str;
    uint64_t output_layout;
    struct ChannelMap map[MAX_CH];
    int nch;
    enum MappingMode mode;
} ChannelMapContext;

#define OFFSET(x) offsetof(ChannelMapContext, x)
#define A AV_OPT_FLAG_AUDIO_PARAM
#define F AV_OPT_FLAG_FILTERING_PARAM
static const AVOption channelmap_options[] = {
    { "map", "A comma-separated list of input channel numbers in output order.",
          OFFSET(mapping_str),        AV_OPT_TYPE_STRING, .flags = A|F },
    { "channel_layout", "Output channel layout.",
          OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, .flags = A|F },
    { NULL }
};

AVFILTER_DEFINE_CLASS(channelmap);

static char* split(char *message, char delim) {
    char *next = strchr(message, delim);
    if (next)
      *next++ = '\0';
    return next;
}

static int get_channel_idx(char **map, int *ch, char delim, int max_ch)
{
    char *next = split(*map, delim);
    int len;
    int n = 0;
    if (!next && delim == '-')
        return AVERROR(EINVAL);
    len = strlen(*map);
    sscanf(*map, "%d%n", ch, &n);
    if (n != len)
        return AVERROR(EINVAL);
    if (*ch < 0 || *ch > max_ch)
        return AVERROR(EINVAL);
    *map = next;
    return 0;
}

static int get_channel(char **map, uint64_t *ch, char delim)
{
    char *next = split(*map, delim);
    if (!next && delim == '-')
        return AVERROR(EINVAL);
    *ch = av_get_channel_layout(*map);
    if (av_get_channel_layout_nb_channels(*ch) != 1)
        return AVERROR(EINVAL);
    *map = next;
    return 0;
}

static av_cold int channelmap_init(AVFilterContext *ctx)
{
    ChannelMapContext *s = ctx->priv;
    char *mapping, separator = '|';
    int map_entries = 0;
    char buf[256];
    enum MappingMode mode;
    uint64_t out_ch_mask = 0;
    int i;

    mapping = s->mapping_str;

    if (!mapping) {
        mode = MAP_NONE;
    } else {
        char *dash = strchr(mapping, '-');
        if (!dash) {  // short mapping
            if (av_isdigit(*mapping))
                mode = MAP_ONE_INT;
            else
                mode = MAP_ONE_STR;
        } else if (av_isdigit(*mapping)) {
            if (av_isdigit(*(dash+1)))
                mode = MAP_PAIR_INT_INT;
            else
                mode = MAP_PAIR_INT_STR;
        } else {
            if (av_isdigit(*(dash+1)))
                mode = MAP_PAIR_STR_INT;
            else
                mode = MAP_PAIR_STR_STR;
        }
#if FF_API_OLD_FILTER_OPTS
        if (strchr(mapping, ',')) {
            av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use "
                   "'|' to separate the mappings.\n");
            separator = ',';
        }
#endif
    }

    if (mode != MAP_NONE) {
        char *sep = mapping;
        map_entries = 1;
        while ((sep = strchr(sep, separator))) {
            if (*++sep)  // Allow trailing comma
                map_entries++;
        }
    }

    if (map_entries > MAX_CH) {
        av_log(ctx, AV_LOG_ERROR, "Too many channels mapped: '%d'.\n", map_entries);
        return AVERROR(EINVAL);
    }

    for (i = 0; i < map_entries; i++) {
        int in_ch_idx = -1, out_ch_idx = -1;
        uint64_t in_ch = 0, out_ch = 0;
        static const char err[] = "Failed to parse channel map\n";
        switch (mode) {
        case MAP_ONE_INT:
            if (get_channel_idx(&mapping, &in_ch_idx, separator, MAX_CH) < 0) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel_idx  = in_ch_idx;
            s->map[i].out_channel_idx = i;
            break;
        case MAP_ONE_STR:
            if (get_channel(&mapping, &in_ch, separator) < 0) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel      = in_ch;
            s->map[i].out_channel_idx = i;
            break;
        case MAP_PAIR_INT_INT:
            if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 ||
                get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel_idx  = in_ch_idx;
            s->map[i].out_channel_idx = out_ch_idx;
            break;
        case MAP_PAIR_INT_STR:
            if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 ||
                get_channel(&mapping, &out_ch, separator) < 0 ||
                out_ch & out_ch_mask) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel_idx  = in_ch_idx;
            s->map[i].out_channel     = out_ch;
            out_ch_mask |= out_ch;
            break;
        case MAP_PAIR_STR_INT:
            if (get_channel(&mapping, &in_ch, '-') < 0 ||
                get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel      = in_ch;
            s->map[i].out_channel_idx = out_ch_idx;
            break;
        case MAP_PAIR_STR_STR:
            if (get_channel(&mapping, &in_ch, '-') < 0 ||
                get_channel(&mapping, &out_ch, separator) < 0 ||
                out_ch & out_ch_mask) {
                av_log(ctx, AV_LOG_ERROR, err);
                return AVERROR(EINVAL);
            }
            s->map[i].in_channel = in_ch;
            s->map[i].out_channel = out_ch;
            out_ch_mask |= out_ch;
            break;
        }
    }
    s->mode          = mode;
    s->nch           = map_entries;
    s->output_layout = out_ch_mask ? out_ch_mask :
                       av_get_default_channel_layout(map_entries);

    if (s->channel_layout_str) {
        uint64_t fmt;
        if ((fmt = av_get_channel_layout(s->channel_layout_str)) == 0) {
            av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout: '%s'.\n",
                   s->channel_layout_str);
            return AVERROR(EINVAL);
        }
        if (mode == MAP_NONE) {
            int i;
            s->nch = av_get_channel_layout_nb_channels(fmt);
            for (i = 0; i < s->nch; i++) {
                s->map[i].in_channel_idx  = i;
                s->map[i].out_channel_idx = i;
            }
        } else if (out_ch_mask && out_ch_mask != fmt) {
            av_get_channel_layout_string(buf, sizeof(buf), 0, out_ch_mask);
            av_log(ctx, AV_LOG_ERROR,
                   "Output channel layout '%s' does not match the list of channel mapped: '%s'.\n",
                   s->channel_layout_str, buf);
            return AVERROR(EINVAL);
        } else if (s->nch != av_get_channel_layout_nb_channels(fmt)) {
            av_log(ctx, AV_LOG_ERROR,
                   "Output channel layout %s does not match the number of channels mapped %d.\n",
                   s->channel_layout_str, s->nch);
            return AVERROR(EINVAL);
        }
        s->output_layout = fmt;
    }
    if (!s->output_layout) {
        av_log(ctx, AV_LOG_ERROR, "Output channel layout is not set and "
               "cannot be guessed from the maps.\n");
        return AVERROR(EINVAL);
    }

    ff_add_channel_layout(&s->channel_layouts, s->output_layout);

    if (mode == MAP_PAIR_INT_STR || mode == MAP_PAIR_STR_STR) {
        for (i = 0; i < s->nch; i++) {
            s->map[i].out_channel_idx = av_get_channel_layout_channel_index(
                s->output_layout, s->map[i].out_channel);
        }
    }

    return 0;
}

static int channelmap_query_formats(AVFilterContext *ctx)
{
    ChannelMapContext *s = ctx->priv;

    ff_set_common_formats(ctx, ff_planar_sample_fmts());
    ff_set_common_samplerates(ctx, ff_all_samplerates());
    ff_channel_layouts_ref(ff_all_channel_layouts(), &ctx->inputs[0]->out_channel_layouts);
    ff_channel_layouts_ref(s->channel_layouts,       &ctx->outputs[0]->in_channel_layouts);

    return 0;
}

static int channelmap_filter_frame(AVFilterLink *inlink, AVFrame *buf)
{
    AVFilterContext  *ctx = inlink->dst;
    AVFilterLink *outlink = ctx->outputs[0];
    const ChannelMapContext *s = ctx->priv;
    const int nch_in = av_get_channel_layout_nb_channels(inlink->channel_layout);
    const int nch_out = s->nch;
    int ch;
    uint8_t *source_planes[MAX_CH];

    memcpy(source_planes, buf->extended_data,
           nch_in * sizeof(source_planes[0]));

    if (nch_out > nch_in) {
        if (nch_out > FF_ARRAY_ELEMS(buf->data)) {
            uint8_t **new_extended_data =
                av_mallocz_array(nch_out, sizeof(*buf->extended_data));
            if (!new_extended_data) {
                av_frame_free(&buf);
                return AVERROR(ENOMEM);
            }
            if (buf->extended_data == buf->data) {
                buf->extended_data = new_extended_data;
            } else {
                av_free(buf->extended_data);
                buf->extended_data = new_extended_data;
            }
        } else if (buf->extended_data != buf->data) {
            av_free(buf->extended_data);
            buf->extended_data = buf->data;
        }
    }

    for (ch = 0; ch < nch_out; ch++) {
        buf->extended_data[s->map[ch].out_channel_idx] =
            source_planes[s->map[ch].in_channel_idx];
    }

    if (buf->data != buf->extended_data)
        memcpy(buf->data, buf->extended_data,
           FFMIN(FF_ARRAY_ELEMS(buf->data), nch_out) * sizeof(buf->data[0]));

    buf->channel_layout = outlink->channel_layout;

    return ff_filter_frame(outlink, buf);
}

static int channelmap_config_input(AVFilterLink *inlink)
{
    AVFilterContext *ctx = inlink->dst;
    ChannelMapContext *s = ctx->priv;
    int nb_channels = av_get_channel_layout_nb_channels(inlink->channel_layout);
    int i, err = 0;
    const char *channel_name;
    char layout_name[256];

    for (i = 0; i < s->nch; i++) {
        struct ChannelMap *m = &s->map[i];

        if (s->mode == MAP_PAIR_STR_INT || s->mode == MAP_PAIR_STR_STR) {
            m->in_channel_idx = av_get_channel_layout_channel_index(
                inlink->channel_layout, m->in_channel);
        }

        if (m->in_channel_idx < 0 || m->in_channel_idx >= nb_channels) {
            av_get_channel_layout_string(layout_name, sizeof(layout_name),
                                         0, inlink->channel_layout);
            if (m->in_channel) {
                channel_name = av_get_channel_name(m->in_channel);
                av_log(ctx, AV_LOG_ERROR,
                       "input channel '%s' not available from input layout '%s'\n",
                       channel_name, layout_name);
            } else {
                av_log(ctx, AV_LOG_ERROR,
                       "input channel #%d not available from input layout '%s'\n",
                       m->in_channel_idx, layout_name);
            }
            err = AVERROR(EINVAL);
        }
    }

    return err;
}

static const AVFilterPad avfilter_af_channelmap_inputs[] = {
    {
        .name           = "default",
        .type           = AVMEDIA_TYPE_AUDIO,
        .filter_frame   = channelmap_filter_frame,
        .config_props   = channelmap_config_input,
        .needs_writable = 1,
    },
    { NULL }
};

static const AVFilterPad avfilter_af_channelmap_outputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_AUDIO
    },
    { NULL }
};

AVFilter ff_af_channelmap = {
    .name          = "channelmap",
    .description   = NULL_IF_CONFIG_SMALL("Remap audio channels."),
    .init          = channelmap_init,
    .query_formats = channelmap_query_formats,
    .priv_size     = sizeof(ChannelMapContext),
    .priv_class    = &channelmap_class,
    .inputs        = avfilter_af_channelmap_inputs,
    .outputs       = avfilter_af_channelmap_outputs,
};
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* Copyright (c) 2012 Google, Inc.
	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 channel mapping filter
	24	*/
	25
	26	#include <ctype.h>
	27
	28	#include "libavutil/avstring.h"
	29	#include "libavutil/channel_layout.h"
	30	#include "libavutil/common.h"
	31	#include "libavutil/mathematics.h"
	32	#include "libavutil/opt.h"
	33	#include "libavutil/samplefmt.h"
	34
	35	#include "audio.h"
	36	#include "avfilter.h"
	37	#include "formats.h"
	38	#include "internal.h"
	39
	40	struct ChannelMap {
	41	uint64_t in_channel;
	42	uint64_t out_channel;
	43	int in_channel_idx;
	44	int out_channel_idx;
	45	};
	46
	47	enum MappingMode {
	48	MAP_NONE,
	49	MAP_ONE_INT,
	50	MAP_ONE_STR,
	51	MAP_PAIR_INT_INT,
	52	MAP_PAIR_INT_STR,
	53	MAP_PAIR_STR_INT,
	54	MAP_PAIR_STR_STR
	55	};
	56
	57	#define MAX_CH 64
	58	typedef struct ChannelMapContext {
	59	const AVClass *class;
	60	AVFilterChannelLayouts *channel_layouts;
	61	char *mapping_str;
	62	char *channel_layout_str;
	63	uint64_t output_layout;
	64	struct ChannelMap map[MAX_CH];
65	int nch;
66	enum MappingMode mode;
67	} ChannelMapContext;
68
69	#define OFFSET(x) offsetof(ChannelMapContext, x)
70	#define A AV_OPT_FLAG_AUDIO_PARAM
71	#define F AV_OPT_FLAG_FILTERING_PARAM
72	static const AVOption channelmap_options[] = {
73	{ "map", "A comma-separated list of input channel numbers in output order.",
74	OFFSET(mapping_str), AV_OPT_TYPE_STRING, .flags = A\|F },
75	{ "channel_layout", "Output channel layout.",
76	OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, .flags = A\|F },
77	{ NULL }
78	};
79
80	AVFILTER_DEFINE_CLASS(channelmap);
81
82	static char* split(char *message, char delim) {
83	char *next = strchr(message, delim);
84	if (next)
85	*next++ = '\0';
86	return next;
87	}
88
89	static int get_channel_idx(char *map, int ch, char delim, int max_ch)
90	{
91	char next = split(map, delim);
92	int len;
93	int n = 0;
94	if (!next && delim == '-')
95	return AVERROR(EINVAL);
96	len = strlen(*map);
97	sscanf(*map, "%d%n", ch, &n);
98	if (n != len)
99	return AVERROR(EINVAL);
100	if (ch < 0 \|\| ch > max_ch)
101	return AVERROR(EINVAL);
102	*map = next;
103	return 0;
104	}
105
106	static int get_channel(char *map, uint64_t ch, char delim)
107	{
108	char next = split(map, delim);
109	if (!next && delim == '-')
110	return AVERROR(EINVAL);
111	ch = av_get_channel_layout(map);
112	if (av_get_channel_layout_nb_channels(*ch) != 1)
113	return AVERROR(EINVAL);
114	*map = next;
115	return 0;
116	}
117
118	static av_cold int channelmap_init(AVFilterContext *ctx)
119	{
120	ChannelMapContext *s = ctx->priv;
121	char *mapping, separator = '\|';
122	int map_entries = 0;
123	char buf[256];
124	enum MappingMode mode;
125	uint64_t out_ch_mask = 0;
126	int i;
127
128	mapping = s->mapping_str;
129
130	if (!mapping) {
131	mode = MAP_NONE;
132	} else {
133	char *dash = strchr(mapping, '-');
134	if (!dash) { // short mapping
135	if (av_isdigit(*mapping))
136	mode = MAP_ONE_INT;
137	else
138	mode = MAP_ONE_STR;
139	} else if (av_isdigit(*mapping)) {
140	if (av_isdigit(*(dash+1)))
141	mode = MAP_PAIR_INT_INT;
142	else
143	mode = MAP_PAIR_INT_STR;
144	} else {
145	if (av_isdigit(*(dash+1)))
146	mode = MAP_PAIR_STR_INT;
147	else
148	mode = MAP_PAIR_STR_STR;
149	}
150	#if FF_API_OLD_FILTER_OPTS
151	if (strchr(mapping, ',')) {
152	av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use "
153	"'\|' to separate the mappings.\n");
154	separator = ',';
155	}
156	#endif
157	}
158
159	if (mode != MAP_NONE) {
160	char *sep = mapping;
161	map_entries = 1;
162	while ((sep = strchr(sep, separator))) {
163	if (*++sep) // Allow trailing comma
164	map_entries++;
165	}
166	}
167
168	if (map_entries > MAX_CH) {
169	av_log(ctx, AV_LOG_ERROR, "Too many channels mapped: '%d'.\n", map_entries);
170	return AVERROR(EINVAL);
171	}
172
173	for (i = 0; i < map_entries; i++) {
174	int in_ch_idx = -1, out_ch_idx = -1;
175	uint64_t in_ch = 0, out_ch = 0;
176	static const char err[] = "Failed to parse channel map\n";
177	switch (mode) {
178	case MAP_ONE_INT:
179	if (get_channel_idx(&mapping, &in_ch_idx, separator, MAX_CH) < 0) {
180	av_log(ctx, AV_LOG_ERROR, err);
181	return AVERROR(EINVAL);
182	}
183	s->map[i].in_channel_idx = in_ch_idx;
184	s->map[i].out_channel_idx = i;
185	break;
186	case MAP_ONE_STR:
187	if (get_channel(&mapping, &in_ch, separator) < 0) {
188	av_log(ctx, AV_LOG_ERROR, err);
189	return AVERROR(EINVAL);
190	}
191	s->map[i].in_channel = in_ch;
192	s->map[i].out_channel_idx = i;
193	break;
194	case MAP_PAIR_INT_INT:
195	if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 \|\|
196	get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) {
197	av_log(ctx, AV_LOG_ERROR, err);
198	return AVERROR(EINVAL);
199	}
200	s->map[i].in_channel_idx = in_ch_idx;
201	s->map[i].out_channel_idx = out_ch_idx;
202	break;
203	case MAP_PAIR_INT_STR:
204	if (get_channel_idx(&mapping, &in_ch_idx, '-', MAX_CH) < 0 \|\|
205	get_channel(&mapping, &out_ch, separator) < 0 \|\|
206	out_ch & out_ch_mask) {
207	av_log(ctx, AV_LOG_ERROR, err);
208	return AVERROR(EINVAL);
209	}
210	s->map[i].in_channel_idx = in_ch_idx;
211	s->map[i].out_channel = out_ch;
212	out_ch_mask \|= out_ch;
213	break;
214	case MAP_PAIR_STR_INT:
215	if (get_channel(&mapping, &in_ch, '-') < 0 \|\|
216	get_channel_idx(&mapping, &out_ch_idx, separator, MAX_CH) < 0) {
217	av_log(ctx, AV_LOG_ERROR, err);
218	return AVERROR(EINVAL);
219	}
220	s->map[i].in_channel = in_ch;
221	s->map[i].out_channel_idx = out_ch_idx;
222	break;
223	case MAP_PAIR_STR_STR:
224	if (get_channel(&mapping, &in_ch, '-') < 0 \|\|
225	get_channel(&mapping, &out_ch, separator) < 0 \|\|
226	out_ch & out_ch_mask) {
227	av_log(ctx, AV_LOG_ERROR, err);
228	return AVERROR(EINVAL);
229	}
230	s->map[i].in_channel = in_ch;
231	s->map[i].out_channel = out_ch;
232	out_ch_mask \|= out_ch;
233	break;
234	}
235	}
236	s->mode = mode;
237	s->nch = map_entries;
238	s->output_layout = out_ch_mask ? out_ch_mask :
239	av_get_default_channel_layout(map_entries);
240
241	if (s->channel_layout_str) {
242	uint64_t fmt;
243	if ((fmt = av_get_channel_layout(s->channel_layout_str)) == 0) {
244	av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout: '%s'.\n",
245	s->channel_layout_str);
246	return AVERROR(EINVAL);
247	}
248	if (mode == MAP_NONE) {
249	int i;
250	s->nch = av_get_channel_layout_nb_channels(fmt);
251	for (i = 0; i < s->nch; i++) {
252	s->map[i].in_channel_idx = i;
253	s->map[i].out_channel_idx = i;
254	}
255	} else if (out_ch_mask && out_ch_mask != fmt) {
256	av_get_channel_layout_string(buf, sizeof(buf), 0, out_ch_mask);
257	av_log(ctx, AV_LOG_ERROR,
258	"Output channel layout '%s' does not match the list of channel mapped: '%s'.\n",
259	s->channel_layout_str, buf);
260	return AVERROR(EINVAL);
261	} else if (s->nch != av_get_channel_layout_nb_channels(fmt)) {
262	av_log(ctx, AV_LOG_ERROR,
263	"Output channel layout %s does not match the number of channels mapped %d.\n",
264	s->channel_layout_str, s->nch);
265	return AVERROR(EINVAL);
266	}
267	s->output_layout = fmt;
268	}
269	if (!s->output_layout) {
270	av_log(ctx, AV_LOG_ERROR, "Output channel layout is not set and "
271	"cannot be guessed from the maps.\n");
272	return AVERROR(EINVAL);
273	}
274
275	ff_add_channel_layout(&s->channel_layouts, s->output_layout);
276
277	if (mode == MAP_PAIR_INT_STR \|\| mode == MAP_PAIR_STR_STR) {
278	for (i = 0; i < s->nch; i++) {
279	s->map[i].out_channel_idx = av_get_channel_layout_channel_index(
280	s->output_layout, s->map[i].out_channel);
281	}
282	}
283
284	return 0;
285	}
286
287	static int channelmap_query_formats(AVFilterContext *ctx)
288	{
289	ChannelMapContext *s = ctx->priv;
290
291	ff_set_common_formats(ctx, ff_planar_sample_fmts());
292	ff_set_common_samplerates(ctx, ff_all_samplerates());
293	ff_channel_layouts_ref(ff_all_channel_layouts(), &ctx->inputs[0]->out_channel_layouts);
294	ff_channel_layouts_ref(s->channel_layouts, &ctx->outputs[0]->in_channel_layouts);
295
296	return 0;
297	}
298
299	static int channelmap_filter_frame(AVFilterLink inlink, AVFrame buf)
300	{
301	AVFilterContext *ctx = inlink->dst;
302	AVFilterLink *outlink = ctx->outputs[0];
303	const ChannelMapContext *s = ctx->priv;
304	const int nch_in = av_get_channel_layout_nb_channels(inlink->channel_layout);
305	const int nch_out = s->nch;
306	int ch;
307	uint8_t *source_planes[MAX_CH];
308
309	memcpy(source_planes, buf->extended_data,
310	nch_in * sizeof(source_planes[0]));
311
312	if (nch_out > nch_in) {
313	if (nch_out > FF_ARRAY_ELEMS(buf->data)) {
314	uint8_t **new_extended_data =
315	av_mallocz_array(nch_out, sizeof(*buf->extended_data));
316	if (!new_extended_data) {
317	av_frame_free(&buf);
318	return AVERROR(ENOMEM);
319	}
320	if (buf->extended_data == buf->data) {
321	buf->extended_data = new_extended_data;
322	} else {
323	av_free(buf->extended_data);
324	buf->extended_data = new_extended_data;
325	}
326	} else if (buf->extended_data != buf->data) {
327	av_free(buf->extended_data);
328	buf->extended_data = buf->data;
329	}
330	}
331
332	for (ch = 0; ch < nch_out; ch++) {
333	buf->extended_data[s->map[ch].out_channel_idx] =
334	source_planes[s->map[ch].in_channel_idx];
335	}
336
337	if (buf->data != buf->extended_data)
338	memcpy(buf->data, buf->extended_data,
339	FFMIN(FF_ARRAY_ELEMS(buf->data), nch_out) * sizeof(buf->data[0]));
340
341	buf->channel_layout = outlink->channel_layout;
342
343	return ff_filter_frame(outlink, buf);
344	}
345
346	static int channelmap_config_input(AVFilterLink *inlink)
347	{
348	AVFilterContext *ctx = inlink->dst;
349	ChannelMapContext *s = ctx->priv;
350	int nb_channels = av_get_channel_layout_nb_channels(inlink->channel_layout);
351	int i, err = 0;
352	const char *channel_name;
353	char layout_name[256];
354
355	for (i = 0; i < s->nch; i++) {
356	struct ChannelMap *m = &s->map[i];
357
358	if (s->mode == MAP_PAIR_STR_INT \|\| s->mode == MAP_PAIR_STR_STR) {
359	m->in_channel_idx = av_get_channel_layout_channel_index(
360	inlink->channel_layout, m->in_channel);
361	}
362
363	if (m->in_channel_idx < 0 \|\| m->in_channel_idx >= nb_channels) {
364	av_get_channel_layout_string(layout_name, sizeof(layout_name),
365	0, inlink->channel_layout);
366	if (m->in_channel) {
367	channel_name = av_get_channel_name(m->in_channel);
368	av_log(ctx, AV_LOG_ERROR,
369	"input channel '%s' not available from input layout '%s'\n",
370	channel_name, layout_name);
371	} else {
372	av_log(ctx, AV_LOG_ERROR,
373	"input channel #%d not available from input layout '%s'\n",
374	m->in_channel_idx, layout_name);
375	}
376	err = AVERROR(EINVAL);
377	}
378	}
379
380	return err;
381	}
382
383	static const AVFilterPad avfilter_af_channelmap_inputs[] = {
384	{
385	.name = "default",
386	.type = AVMEDIA_TYPE_AUDIO,
387	.filter_frame = channelmap_filter_frame,
388	.config_props = channelmap_config_input,
389	.needs_writable = 1,
390	},
391	{ NULL }
392	};
393
394	static const AVFilterPad avfilter_af_channelmap_outputs[] = {
395	{
396	.name = "default",
397	.type = AVMEDIA_TYPE_AUDIO
398	},
399	{ NULL }
400	};
401
402	AVFilter ff_af_channelmap = {
403	.name = "channelmap",
404	.description = NULL_IF_CONFIG_SMALL("Remap audio channels."),
405	.init = channelmap_init,
406	.query_formats = channelmap_query_formats,
407	.priv_size = sizeof(ChannelMapContext),
408	.priv_class = &channelmap_class,
409	.inputs = avfilter_af_channelmap_inputs,
410	.outputs = avfilter_af_channelmap_outputs,
411	};