From 41e637e44902246efa17babf26e9be8a4a519e6f Mon Sep 17 00:00:00 2001 From: Alex Converse Date: Fri, 8 Jun 2012 18:42:53 -0700 Subject: lavfi: Add the af_channelmap audio channel mapping filter. Inspired by MPlayer's af_channels filter and SoX's remix effect. --- libavfilter/af_channelmap.c | 402 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 402 insertions(+) create mode 100644 libavfilter/af_channelmap.c (limited to 'libavfilter/af_channelmap.c') diff --git a/libavfilter/af_channelmap.c b/libavfilter/af_channelmap.c new file mode 100644 index 0000000..14c2c0c --- /dev/null +++ b/libavfilter/af_channelmap.c @@ -0,0 +1,402 @@ +/* + * Copyright (c) 2012 Google, Inc. + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; 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 + +#include "libavutil/audioconvert.h" +#include "libavutil/avstring.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 +static const AVOption options[] = { + { "map", "A comma-separated list of input channel numbers in output order.", + OFFSET(mapping_str), AV_OPT_TYPE_STRING, .flags = A }, + { "channel_layout", "Output channel layout.", + OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, .flags = A }, + { NULL }, +}; + +static const AVClass channelmap_class = { + .class_name = "channel map filter", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +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, const char *args, + void *opaque) +{ + ChannelMapContext *s = ctx->priv; + int ret; + char *mapping; + enum mode; + int map_entries = 0; + char buf[256]; + enum MappingMode mode; + uint64_t out_ch_mask = 0; + int i; + + if (!args) { + av_log(ctx, AV_LOG_ERROR, "No parameters supplied.\n"); + return AVERROR(EINVAL); + } + + s->class = &channelmap_class; + av_opt_set_defaults(s); + + if ((ret = av_set_options_string(s, args, "=", ":")) < 0) { + av_log(ctx, AV_LOG_ERROR, "Error parsing options string '%s'.\n", args); + return ret; + } + + mapping = s->mapping_str; + + if (!mapping) { + mode = MAP_NONE; + } else { + char *dash = strchr(mapping, '-'); + if (!dash) { // short mapping + if (isdigit(*mapping)) + mode = MAP_ONE_INT; + else + mode = MAP_ONE_STR; + } else if (isdigit(*mapping)) { + if (isdigit(*(dash+1))) + mode = MAP_PAIR_INT_INT; + else + mode = MAP_PAIR_INT_STR; + } else { + if (isdigit(*(dash+1))) + mode = MAP_PAIR_STR_INT; + else + mode = MAP_PAIR_STR_STR; + } + } + + if (mode != MAP_NONE) { + char *comma = mapping; + map_entries = 1; + while ((comma = strchr(comma, ','))) { + if (*++comma) // Allow trailing comma + map_entries++; + } + } + + if (map_entries > MAX_CH) { + av_log(ctx, AV_LOG_ERROR, "Too many channels mapped: '%d'.\n", map_entries); + ret = AVERROR(EINVAL); + goto fail; + } + + 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, ',', MAX_CH) < 0) { + ret = AVERROR(EINVAL); + av_log(ctx, AV_LOG_ERROR, err); + goto fail; + } + 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, ',')) { + av_log(ctx, AV_LOG_ERROR, err); + ret = AVERROR(EINVAL); + goto fail; + } + 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, ',', MAX_CH) < 0) { + av_log(ctx, AV_LOG_ERROR, err); + ret = AVERROR(EINVAL); + goto fail; + } + 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, ',') < 0 || + out_ch & out_ch_mask) { + av_log(ctx, AV_LOG_ERROR, err); + ret = AVERROR(EINVAL); + goto fail; + } + 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, ',', MAX_CH) < 0) { + av_log(ctx, AV_LOG_ERROR, err); + ret = AVERROR(EINVAL); + goto fail; + } + 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, ',') < 0 || + out_ch & out_ch_mask) { + av_log(ctx, AV_LOG_ERROR, err); + ret = AVERROR(EINVAL); + goto fail; + } + 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); + ret = AVERROR(EINVAL); + goto fail; + } + 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); + ret = AVERROR(EINVAL); + goto fail; + } 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); + ret = AVERROR(EINVAL); + goto fail; + } + s->output_layout = fmt; + } + 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); + } + } + +fail: + av_opt_free(s); + return ret; +} + +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 void channelmap_filter_samples(AVFilterLink *inlink, AVFilterBufferRef *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(nch_out * sizeof(*buf->extended_data)); + if (!new_extended_data) + return; + if (buf->extended_data == buf->data) { + buf->extended_data = new_extended_data; + } else { + buf->extended_data = new_extended_data; + av_free(buf->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])); + + ff_filter_samples(outlink, buf); +} + +static int channelmap_config_input(AVFilterLink *inlink) +{ + AVFilterContext *ctx = inlink->dst; + ChannelMapContext *s = ctx->priv; + int i, err = 0; + const char *channel_name; + char layout_name[256]; + + if (s->mode == MAP_PAIR_STR_INT || s->mode == MAP_PAIR_STR_STR) { + for (i = 0; i < s->nch; i++) { + s->map[i].in_channel_idx = av_get_channel_layout_channel_index( + inlink->channel_layout, s->map[i].in_channel); + if (s->map[i].in_channel_idx < 0) { + channel_name = av_get_channel_name(s->map[i].in_channel); + av_get_channel_layout_string(layout_name, sizeof(layout_name), + 0, inlink->channel_layout); + av_log(ctx, AV_LOG_ERROR, + "input channel '%s' not available from input layout '%s'\n", + channel_name, layout_name); + err = AVERROR(EINVAL); + } + } + } + + return err; +} + +AVFilter avfilter_af_channelmap = { + .name = "channelmap", + .description = NULL_IF_CONFIG_SMALL("Remap audio channels."), + .init = channelmap_init, + .query_formats = channelmap_query_formats, + .priv_size = sizeof(ChannelMapContext), + + .inputs = (AVFilterPad[]) {{ .name = "default", + .type = AVMEDIA_TYPE_AUDIO, + .filter_samples = channelmap_filter_samples, + .config_props = channelmap_config_input }, + { .name = NULL }}, + .outputs = (AVFilterPad[]) {{ .name = "default", + .type = AVMEDIA_TYPE_AUDIO }, + { .name = NULL }}, +}; -- cgit v1.1