/* * Copyright (c) 2006 Michael Niedermayer * * 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 layout utility functions */ #include #include #include #include "avassert.h" #include "channel_layout.h" #include "bprint.h" #include "common.h" #include "error.h" #include "macros.h" #include "opt.h" #define CHAN_IS_AMBI(x) ((x) >= AV_CHAN_AMBISONIC_BASE &&\ (x) <= AV_CHAN_AMBISONIC_END) struct channel_name { const char *name; const char *description; }; static const struct channel_name channel_names[] = { [AV_CHAN_FRONT_LEFT ] = { "FL", "front left" }, [AV_CHAN_FRONT_RIGHT ] = { "FR", "front right" }, [AV_CHAN_FRONT_CENTER ] = { "FC", "front center" }, [AV_CHAN_LOW_FREQUENCY ] = { "LFE", "low frequency" }, [AV_CHAN_BACK_LEFT ] = { "BL", "back left" }, [AV_CHAN_BACK_RIGHT ] = { "BR", "back right" }, [AV_CHAN_FRONT_LEFT_OF_CENTER ] = { "FLC", "front left-of-center" }, [AV_CHAN_FRONT_RIGHT_OF_CENTER] = { "FRC", "front right-of-center" }, [AV_CHAN_BACK_CENTER ] = { "BC", "back center" }, [AV_CHAN_SIDE_LEFT ] = { "SL", "side left" }, [AV_CHAN_SIDE_RIGHT ] = { "SR", "side right" }, [AV_CHAN_TOP_CENTER ] = { "TC", "top center" }, [AV_CHAN_TOP_FRONT_LEFT ] = { "TFL", "top front left" }, [AV_CHAN_TOP_FRONT_CENTER ] = { "TFC", "top front center" }, [AV_CHAN_TOP_FRONT_RIGHT ] = { "TFR", "top front right" }, [AV_CHAN_TOP_BACK_LEFT ] = { "TBL", "top back left" }, [AV_CHAN_TOP_BACK_CENTER ] = { "TBC", "top back center" }, [AV_CHAN_TOP_BACK_RIGHT ] = { "TBR", "top back right" }, [AV_CHAN_STEREO_LEFT ] = { "DL", "downmix left" }, [AV_CHAN_STEREO_RIGHT ] = { "DR", "downmix right" }, [AV_CHAN_WIDE_LEFT ] = { "WL", "wide left" }, [AV_CHAN_WIDE_RIGHT ] = { "WR", "wide right" }, [AV_CHAN_SURROUND_DIRECT_LEFT ] = { "SDL", "surround direct left" }, [AV_CHAN_SURROUND_DIRECT_RIGHT] = { "SDR", "surround direct right" }, [AV_CHAN_LOW_FREQUENCY_2 ] = { "LFE2", "low frequency 2" }, [AV_CHAN_TOP_SIDE_LEFT ] = { "TSL", "top side left" }, [AV_CHAN_TOP_SIDE_RIGHT ] = { "TSR", "top side right" }, [AV_CHAN_BOTTOM_FRONT_CENTER ] = { "BFC", "bottom front center" }, [AV_CHAN_BOTTOM_FRONT_LEFT ] = { "BFL", "bottom front left" }, [AV_CHAN_BOTTOM_FRONT_RIGHT ] = { "BFR", "bottom front right" }, }; void av_channel_name_bprint(AVBPrint *bp, enum AVChannel channel_id) { if (channel_id >= AV_CHAN_AMBISONIC_BASE && channel_id <= AV_CHAN_AMBISONIC_END) av_bprintf(bp, "AMBI%d", channel_id - AV_CHAN_AMBISONIC_BASE); else if ((unsigned)channel_id < FF_ARRAY_ELEMS(channel_names) && channel_names[channel_id].name) av_bprintf(bp, "%s", channel_names[channel_id].name); else if (channel_id == AV_CHAN_NONE) av_bprintf(bp, "NONE"); else av_bprintf(bp, "USR%d", channel_id); } int av_channel_name(char *buf, size_t buf_size, enum AVChannel channel_id) { AVBPrint bp; if (!buf && buf_size) return AVERROR(EINVAL); av_bprint_init_for_buffer(&bp, buf, buf_size); av_channel_name_bprint(&bp, channel_id); if (bp.len >= INT_MAX) return AVERROR(ERANGE); return bp.len + 1; } void av_channel_description_bprint(AVBPrint *bp, enum AVChannel channel_id) { if (channel_id >= AV_CHAN_AMBISONIC_BASE && channel_id <= AV_CHAN_AMBISONIC_END) av_bprintf(bp, "ambisonic ACN %d", channel_id - AV_CHAN_AMBISONIC_BASE); else if ((unsigned)channel_id < FF_ARRAY_ELEMS(channel_names) && channel_names[channel_id].description) av_bprintf(bp, "%s", channel_names[channel_id].description); else if (channel_id == AV_CHAN_NONE) av_bprintf(bp, "none"); else av_bprintf(bp, "user %d", channel_id); } int av_channel_description(char *buf, size_t buf_size, enum AVChannel channel_id) { AVBPrint bp; if (!buf && buf_size) return AVERROR(EINVAL); av_bprint_init_for_buffer(&bp, buf, buf_size); av_channel_description_bprint(&bp, channel_id); if (bp.len >= INT_MAX) return AVERROR(ERANGE); return bp.len + 1; } enum AVChannel av_channel_from_string(const char *str) { int i; char *endptr = (char *)str; enum AVChannel id = AV_CHAN_NONE; if (!strncmp(str, "AMBI", 4)) { i = strtol(str + 4, NULL, 0); if (i < 0 || i > AV_CHAN_AMBISONIC_END - AV_CHAN_AMBISONIC_BASE) return AV_CHAN_NONE; return AV_CHAN_AMBISONIC_BASE + i; } for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) { if (channel_names[i].name && !strcmp(str, channel_names[i].name)) return i; } if (!strncmp(str, "USR", 3)) { const char *p = str + 3; id = strtol(p, &endptr, 0); } if (id >= 0 && !*endptr) return id; return AV_CHAN_NONE; } struct channel_layout_name { const char *name; AVChannelLayout layout; }; static const struct channel_layout_name channel_layout_map[] = { { "mono", AV_CHANNEL_LAYOUT_MONO }, { "stereo", AV_CHANNEL_LAYOUT_STEREO }, { "2.1", AV_CHANNEL_LAYOUT_2POINT1 }, { "3.0", AV_CHANNEL_LAYOUT_SURROUND }, { "3.0(back)", AV_CHANNEL_LAYOUT_2_1 }, { "4.0", AV_CHANNEL_LAYOUT_4POINT0 }, { "quad", AV_CHANNEL_LAYOUT_QUAD }, { "quad(side)", AV_CHANNEL_LAYOUT_2_2 }, { "3.1", AV_CHANNEL_LAYOUT_3POINT1 }, { "5.0", AV_CHANNEL_LAYOUT_5POINT0_BACK }, { "5.0(side)", AV_CHANNEL_LAYOUT_5POINT0 }, { "4.1", AV_CHANNEL_LAYOUT_4POINT1 }, { "5.1", AV_CHANNEL_LAYOUT_5POINT1_BACK }, { "5.1(side)", AV_CHANNEL_LAYOUT_5POINT1 }, { "6.0", AV_CHANNEL_LAYOUT_6POINT0 }, { "6.0(front)", AV_CHANNEL_LAYOUT_6POINT0_FRONT }, { "3.1.2", AV_CHANNEL_LAYOUT_3POINT1POINT2 }, { "hexagonal", AV_CHANNEL_LAYOUT_HEXAGONAL }, { "6.1", AV_CHANNEL_LAYOUT_6POINT1 }, { "6.1(back)", AV_CHANNEL_LAYOUT_6POINT1_BACK }, { "6.1(front)", AV_CHANNEL_LAYOUT_6POINT1_FRONT }, { "7.0", AV_CHANNEL_LAYOUT_7POINT0 }, { "7.0(front)", AV_CHANNEL_LAYOUT_7POINT0_FRONT }, { "7.1", AV_CHANNEL_LAYOUT_7POINT1 }, { "7.1(wide)", AV_CHANNEL_LAYOUT_7POINT1_WIDE_BACK }, { "7.1(wide-side)", AV_CHANNEL_LAYOUT_7POINT1_WIDE }, { "5.1.2", AV_CHANNEL_LAYOUT_5POINT1POINT2_BACK }, { "octagonal", AV_CHANNEL_LAYOUT_OCTAGONAL }, { "cube", AV_CHANNEL_LAYOUT_CUBE }, { "5.1.4", AV_CHANNEL_LAYOUT_5POINT1POINT4_BACK }, { "7.1.2", AV_CHANNEL_LAYOUT_7POINT1POINT2 }, { "7.1.4", AV_CHANNEL_LAYOUT_7POINT1POINT4_BACK }, { "7.2.3", AV_CHANNEL_LAYOUT_7POINT2POINT3 }, { "9.1.4", AV_CHANNEL_LAYOUT_9POINT1POINT4_BACK }, { "hexadecagonal", AV_CHANNEL_LAYOUT_HEXADECAGONAL }, { "downmix", AV_CHANNEL_LAYOUT_STEREO_DOWNMIX, }, { "22.2", AV_CHANNEL_LAYOUT_22POINT2, }, }; int av_channel_layout_custom_init(AVChannelLayout *channel_layout, int nb_channels) { AVChannelCustom *map; if (nb_channels <= 0) return AVERROR(EINVAL); map = av_calloc(nb_channels, sizeof(*channel_layout->u.map)); if (!map) return AVERROR(ENOMEM); for (int i = 0; i < nb_channels; i++) map[i].id = AV_CHAN_UNKNOWN; channel_layout->order = AV_CHANNEL_ORDER_CUSTOM; channel_layout->nb_channels = nb_channels; channel_layout->u.map = map; return 0; } int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask) { if (!mask) return AVERROR(EINVAL); channel_layout->order = AV_CHANNEL_ORDER_NATIVE; channel_layout->nb_channels = av_popcount64(mask); channel_layout->u.mask = mask; return 0; } static int parse_channel_list(AVChannelLayout *ch_layout, const char *str) { int ret; int nb_channels = 0; AVChannelCustom *map = NULL; AVChannelCustom custom = {0}; while (*str) { char *channel, *chname; int ret = av_opt_get_key_value(&str, "@", "+", AV_OPT_FLAG_IMPLICIT_KEY, &channel, &chname); if (ret < 0) { av_freep(&map); return ret; } if (*str) str++; // skip separator if (!channel) { channel = chname; chname = NULL; } av_strlcpy(custom.name, chname ? chname : "", sizeof(custom.name)); custom.id = av_channel_from_string(channel); av_free(channel); av_free(chname); if (custom.id == AV_CHAN_NONE) { av_freep(&map); return AVERROR(EINVAL); } av_dynarray2_add((void **)&map, &nb_channels, sizeof(custom), (void *)&custom); if (!map) return AVERROR(ENOMEM); } if (!nb_channels) return AVERROR(EINVAL); ch_layout->order = AV_CHANNEL_ORDER_CUSTOM; ch_layout->u.map = map; ch_layout->nb_channels = nb_channels; ret = av_channel_layout_retype(ch_layout, 0, AV_CHANNEL_LAYOUT_RETYPE_FLAG_CANONICAL); av_assert0(ret == 0); return 0; } int av_channel_layout_from_string(AVChannelLayout *channel_layout, const char *str) { int i, matches, ret; int channels = 0, nb_channels = 0; char *chlist, *end; uint64_t mask = 0; /* channel layout names */ for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) { if (channel_layout_map[i].name && !strcmp(str, channel_layout_map[i].name)) { *channel_layout = channel_layout_map[i].layout; return 0; } } /* This function is a channel layout initializer, so we have to * zero-initialize before we start setting fields individually. */ memset(channel_layout, 0, sizeof(*channel_layout)); /* ambisonic */ if (!strncmp(str, "ambisonic ", 10)) { const char *p = str + 10; char *endptr; AVChannelLayout extra = {0}; int order; order = strtol(p, &endptr, 0); if (order < 0 || order + 1 > INT_MAX / (order + 1) || (*endptr && *endptr != '+')) return AVERROR(EINVAL); channel_layout->order = AV_CHANNEL_ORDER_AMBISONIC; channel_layout->nb_channels = (order + 1) * (order + 1); if (*endptr) { int ret = av_channel_layout_from_string(&extra, endptr + 1); if (ret < 0) return ret; if (extra.nb_channels >= INT_MAX - channel_layout->nb_channels) { av_channel_layout_uninit(&extra); return AVERROR(EINVAL); } if (extra.order == AV_CHANNEL_ORDER_NATIVE) { channel_layout->u.mask = extra.u.mask; } else { channel_layout->order = AV_CHANNEL_ORDER_CUSTOM; channel_layout->u.map = av_calloc(channel_layout->nb_channels + extra.nb_channels, sizeof(*channel_layout->u.map)); if (!channel_layout->u.map) { av_channel_layout_uninit(&extra); return AVERROR(ENOMEM); } for (i = 0; i < channel_layout->nb_channels; i++) channel_layout->u.map[i].id = AV_CHAN_AMBISONIC_BASE + i; for (i = 0; i < extra.nb_channels; i++) { enum AVChannel ch = av_channel_layout_channel_from_index(&extra, i); if (CHAN_IS_AMBI(ch)) { av_channel_layout_uninit(channel_layout); av_channel_layout_uninit(&extra); return AVERROR(EINVAL); } channel_layout->u.map[channel_layout->nb_channels + i].id = ch; if (extra.order == AV_CHANNEL_ORDER_CUSTOM && extra.u.map[i].name[0]) av_strlcpy(channel_layout->u.map[channel_layout->nb_channels + i].name, extra.u.map[i].name, sizeof(channel_layout->u.map[channel_layout->nb_channels + i].name)); } } channel_layout->nb_channels += extra.nb_channels; av_channel_layout_uninit(&extra); } return 0; } chlist = av_strdup(str); if (!chlist) return AVERROR(ENOMEM); /* channel names */ matches = av_sscanf(str, "%d channels (%[^)]", &nb_channels, chlist); ret = parse_channel_list(channel_layout, chlist); av_freep(&chlist); if (ret < 0 && ret != AVERROR(EINVAL)) return ret; if (ret >= 0) { end = strchr(str, ')'); if (matches == 2 && (nb_channels != channel_layout->nb_channels || !end || *++end)) { av_channel_layout_uninit(channel_layout); return AVERROR(EINVAL); } return 0; } errno = 0; mask = strtoull(str, &end, 0); /* channel layout mask */ if (!errno && !*end && !strchr(str, '-') && mask) { av_channel_layout_from_mask(channel_layout, mask); return 0; } errno = 0; channels = strtol(str, &end, 10); /* number of channels */ if (!errno && !strcmp(end, "c") && channels > 0) { av_channel_layout_default(channel_layout, channels); if (channel_layout->order == AV_CHANNEL_ORDER_NATIVE) return 0; } /* number of unordered channels */ if (!errno && (!strcmp(end, "C") || !strcmp(end, " channels")) && channels > 0) { channel_layout->order = AV_CHANNEL_ORDER_UNSPEC; channel_layout->nb_channels = channels; return 0; } return AVERROR(EINVAL); } void av_channel_layout_uninit(AVChannelLayout *channel_layout) { if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) av_freep(&channel_layout->u.map); memset(channel_layout, 0, sizeof(*channel_layout)); } int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src) { av_channel_layout_uninit(dst); *dst = *src; if (src->order == AV_CHANNEL_ORDER_CUSTOM) { dst->u.map = av_malloc_array(src->nb_channels, sizeof(*dst->u.map)); if (!dst->u.map) return AVERROR(ENOMEM); memcpy(dst->u.map, src->u.map, src->nb_channels * sizeof(*src->u.map)); } return 0; } static int64_t masked_description(const AVChannelLayout *channel_layout, int start_channel) { uint64_t mask = 0; for (int i = start_channel; i < channel_layout->nb_channels; i++) { enum AVChannel ch = channel_layout->u.map[i].id; if (ch >= 0 && ch < 63 && mask < (1ULL << ch)) mask |= (1ULL << ch); else return AVERROR(EINVAL); } return mask; } static int has_channel_names(const AVChannelLayout *channel_layout) { if (channel_layout->order != AV_CHANNEL_ORDER_CUSTOM) return 0; for (int i = 0; i < channel_layout->nb_channels; i++) if (channel_layout->u.map[i].name[0]) return 1; return 0; } /** * If the layout is n-th order standard-order ambisonic, with optional * extra non-diegetic channels at the end, return the order. * Return a negative error code otherwise. */ static int ambisonic_order(const AVChannelLayout *channel_layout) { int i, highest_ambi, order; highest_ambi = -1; if (channel_layout->order == AV_CHANNEL_ORDER_AMBISONIC) highest_ambi = channel_layout->nb_channels - av_popcount64(channel_layout->u.mask) - 1; else { const AVChannelCustom *map = channel_layout->u.map; av_assert0(channel_layout->order == AV_CHANNEL_ORDER_CUSTOM); for (i = 0; i < channel_layout->nb_channels; i++) { int is_ambi = CHAN_IS_AMBI(map[i].id); /* ambisonic following non-ambisonic */ if (i > 0 && is_ambi && !CHAN_IS_AMBI(map[i - 1].id)) return AVERROR(EINVAL); /* non-default ordering */ if (is_ambi && map[i].id - AV_CHAN_AMBISONIC_BASE != i) return AVERROR(EINVAL); if (CHAN_IS_AMBI(map[i].id)) highest_ambi = i; } } /* no ambisonic channels*/ if (highest_ambi < 0) return AVERROR(EINVAL); order = floor(sqrt(highest_ambi)); /* incomplete order - some harmonics are missing */ if ((order + 1) * (order + 1) != highest_ambi + 1) return AVERROR(EINVAL); return order; } static enum AVChannelOrder canonical_order(AVChannelLayout *channel_layout) { int has_known_channel = 0; int order; if (channel_layout->order != AV_CHANNEL_ORDER_CUSTOM) return channel_layout->order; if (has_channel_names(channel_layout)) return AV_CHANNEL_ORDER_CUSTOM; for (int i = 0; i < channel_layout->nb_channels && !has_known_channel; i++) if (channel_layout->u.map[i].id != AV_CHAN_UNKNOWN) has_known_channel = 1; if (!has_known_channel) return AV_CHANNEL_ORDER_UNSPEC; if (masked_description(channel_layout, 0) > 0) return AV_CHANNEL_ORDER_NATIVE; order = ambisonic_order(channel_layout); if (order >= 0 && masked_description(channel_layout, (order + 1) * (order + 1)) >= 0) return AV_CHANNEL_ORDER_AMBISONIC; return AV_CHANNEL_ORDER_CUSTOM; } /** * If the custom layout is n-th order standard-order ambisonic, with optional * extra non-diegetic channels at the end, write its string description in bp. * Return a negative error code otherwise. */ static int try_describe_ambisonic(AVBPrint *bp, const AVChannelLayout *channel_layout) { int nb_ambi_channels; int order = ambisonic_order(channel_layout); if (order < 0) return order; av_bprintf(bp, "ambisonic %d", order); /* extra channels present */ nb_ambi_channels = (order + 1) * (order + 1); if (nb_ambi_channels < channel_layout->nb_channels) { AVChannelLayout extra = { 0 }; if (channel_layout->order == AV_CHANNEL_ORDER_AMBISONIC) { extra.order = AV_CHANNEL_ORDER_NATIVE; extra.nb_channels = av_popcount64(channel_layout->u.mask); extra.u.mask = channel_layout->u.mask; } else { int64_t mask; if (!has_channel_names(channel_layout) && (mask = masked_description(channel_layout, nb_ambi_channels)) > 0) { extra.order = AV_CHANNEL_ORDER_NATIVE; extra.nb_channels = av_popcount64(mask); extra.u.mask = mask; } else { extra.order = AV_CHANNEL_ORDER_CUSTOM; extra.nb_channels = channel_layout->nb_channels - nb_ambi_channels; extra.u.map = channel_layout->u.map + nb_ambi_channels; } } av_bprint_chars(bp, '+', 1); av_channel_layout_describe_bprint(&extra, bp); /* Not calling uninit here on extra because we don't own the u.map pointer */ } return 0; } int av_channel_layout_describe_bprint(const AVChannelLayout *channel_layout, AVBPrint *bp) { int i; switch (channel_layout->order) { case AV_CHANNEL_ORDER_NATIVE: for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) if (channel_layout->u.mask == channel_layout_map[i].layout.u.mask) { av_bprintf(bp, "%s", channel_layout_map[i].name); return 0; } // fall-through case AV_CHANNEL_ORDER_CUSTOM: if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) { int64_t mask; int res = try_describe_ambisonic(bp, channel_layout); if (res >= 0) return 0; if (!has_channel_names(channel_layout) && (mask = masked_description(channel_layout, 0)) > 0) { AVChannelLayout native = { .order = AV_CHANNEL_ORDER_NATIVE, .nb_channels = av_popcount64(mask), .u.mask = mask }; return av_channel_layout_describe_bprint(&native, bp); } } if (channel_layout->nb_channels) av_bprintf(bp, "%d channels (", channel_layout->nb_channels); for (i = 0; i < channel_layout->nb_channels; i++) { enum AVChannel ch = av_channel_layout_channel_from_index(channel_layout, i); if (i) av_bprintf(bp, "+"); av_channel_name_bprint(bp, ch); if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM && channel_layout->u.map[i].name[0]) av_bprintf(bp, "@%s", channel_layout->u.map[i].name); } if (channel_layout->nb_channels) { av_bprintf(bp, ")"); return 0; } // fall-through case AV_CHANNEL_ORDER_UNSPEC: av_bprintf(bp, "%d channels", channel_layout->nb_channels); return 0; case AV_CHANNEL_ORDER_AMBISONIC: return try_describe_ambisonic(bp, channel_layout); default: return AVERROR(EINVAL); } } int av_channel_layout_describe(const AVChannelLayout *channel_layout, char *buf, size_t buf_size) { AVBPrint bp; int ret; if (!buf && buf_size) return AVERROR(EINVAL); av_bprint_init_for_buffer(&bp, buf, buf_size); ret = av_channel_layout_describe_bprint(channel_layout, &bp); if (ret < 0) return ret; if (bp.len >= INT_MAX) return AVERROR(ERANGE); return bp.len + 1; } enum AVChannel av_channel_layout_channel_from_index(const AVChannelLayout *channel_layout, unsigned int idx) { int i; if (idx >= channel_layout->nb_channels) return AV_CHAN_NONE; switch (channel_layout->order) { case AV_CHANNEL_ORDER_CUSTOM: return channel_layout->u.map[idx].id; case AV_CHANNEL_ORDER_AMBISONIC: { int ambi_channels = channel_layout->nb_channels - av_popcount64(channel_layout->u.mask); if (idx < ambi_channels) return AV_CHAN_AMBISONIC_BASE + idx; idx -= ambi_channels; } // fall-through case AV_CHANNEL_ORDER_NATIVE: for (i = 0; i < 64; i++) { if ((1ULL << i) & channel_layout->u.mask && !idx--) return i; } default: return AV_CHAN_NONE; } } enum AVChannel av_channel_layout_channel_from_string(const AVChannelLayout *channel_layout, const char *str) { int index = av_channel_layout_index_from_string(channel_layout, str); if (index < 0) return AV_CHAN_NONE; return av_channel_layout_channel_from_index(channel_layout, index); } int av_channel_layout_index_from_channel(const AVChannelLayout *channel_layout, enum AVChannel channel) { int i; if (channel == AV_CHAN_NONE) return AVERROR(EINVAL); switch (channel_layout->order) { case AV_CHANNEL_ORDER_CUSTOM: for (i = 0; i < channel_layout->nb_channels; i++) if (channel_layout->u.map[i].id == channel) return i; return AVERROR(EINVAL); case AV_CHANNEL_ORDER_AMBISONIC: case AV_CHANNEL_ORDER_NATIVE: { uint64_t mask = channel_layout->u.mask; int ambi_channels = channel_layout->nb_channels - av_popcount64(mask); if (channel_layout->order == AV_CHANNEL_ORDER_AMBISONIC && channel >= AV_CHAN_AMBISONIC_BASE) { if (channel - AV_CHAN_AMBISONIC_BASE >= ambi_channels) return AVERROR(EINVAL); return channel - AV_CHAN_AMBISONIC_BASE; } if ((unsigned)channel > 63 || !(mask & (1ULL << channel))) return AVERROR(EINVAL); mask &= (1ULL << channel) - 1; return av_popcount64(mask) + ambi_channels; } default: return AVERROR(EINVAL); } } int av_channel_layout_index_from_string(const AVChannelLayout *channel_layout, const char *str) { char *chname; enum AVChannel ch = AV_CHAN_NONE; switch (channel_layout->order) { case AV_CHANNEL_ORDER_CUSTOM: chname = strstr(str, "@"); if (chname) { char buf[16]; chname++; av_strlcpy(buf, str, FFMIN(sizeof(buf), chname - str)); if (!*chname) chname = NULL; ch = av_channel_from_string(buf); if (ch == AV_CHAN_NONE && *buf) return AVERROR(EINVAL); } for (int i = 0; chname && i < channel_layout->nb_channels; i++) { if (!strcmp(chname, channel_layout->u.map[i].name) && (ch == AV_CHAN_NONE || ch == channel_layout->u.map[i].id)) return i; } // fall-through case AV_CHANNEL_ORDER_AMBISONIC: case AV_CHANNEL_ORDER_NATIVE: ch = av_channel_from_string(str); if (ch == AV_CHAN_NONE) return AVERROR(EINVAL); return av_channel_layout_index_from_channel(channel_layout, ch); } return AVERROR(EINVAL); } int av_channel_layout_check(const AVChannelLayout *channel_layout) { if (channel_layout->nb_channels <= 0) return 0; switch (channel_layout->order) { case AV_CHANNEL_ORDER_NATIVE: return av_popcount64(channel_layout->u.mask) == channel_layout->nb_channels; case AV_CHANNEL_ORDER_CUSTOM: if (!channel_layout->u.map) return 0; for (int i = 0; i < channel_layout->nb_channels; i++) { if (channel_layout->u.map[i].id == AV_CHAN_NONE) return 0; } return 1; case AV_CHANNEL_ORDER_AMBISONIC: /* If non-diegetic channels are present, ensure they are taken into account */ return av_popcount64(channel_layout->u.mask) < channel_layout->nb_channels; case AV_CHANNEL_ORDER_UNSPEC: return 1; default: return 0; } } int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1) { int i; /* different channel counts -> not equal */ if (chl->nb_channels != chl1->nb_channels) return 1; /* if only one is unspecified -> not equal */ if ((chl->order == AV_CHANNEL_ORDER_UNSPEC) != (chl1->order == AV_CHANNEL_ORDER_UNSPEC)) return 1; /* both are unspecified -> equal */ else if (chl->order == AV_CHANNEL_ORDER_UNSPEC) return 0; /* can compare masks directly */ if ((chl->order == AV_CHANNEL_ORDER_NATIVE || chl->order == AV_CHANNEL_ORDER_AMBISONIC) && chl->order == chl1->order) return chl->u.mask != chl1->u.mask; /* compare channel by channel */ for (i = 0; i < chl->nb_channels; i++) if (av_channel_layout_channel_from_index(chl, i) != av_channel_layout_channel_from_index(chl1, i)) return 1; return 0; } void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels) { int i; for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) if (nb_channels == channel_layout_map[i].layout.nb_channels) { *ch_layout = channel_layout_map[i].layout; return; } ch_layout->order = AV_CHANNEL_ORDER_UNSPEC; ch_layout->nb_channels = nb_channels; } const AVChannelLayout *av_channel_layout_standard(void **opaque) { uintptr_t i = (uintptr_t)*opaque; const AVChannelLayout *ch_layout = NULL; if (i < FF_ARRAY_ELEMS(channel_layout_map)) { ch_layout = &channel_layout_map[i].layout; *opaque = (void*)(i + 1); } return ch_layout; } uint64_t av_channel_layout_subset(const AVChannelLayout *channel_layout, uint64_t mask) { uint64_t ret = 0; int i; switch (channel_layout->order) { case AV_CHANNEL_ORDER_NATIVE: case AV_CHANNEL_ORDER_AMBISONIC: return channel_layout->u.mask & mask; case AV_CHANNEL_ORDER_CUSTOM: for (i = 0; i < 64; i++) if (mask & (1ULL << i) && av_channel_layout_index_from_channel(channel_layout, i) >= 0) ret |= (1ULL << i); break; } return ret; } int av_channel_layout_retype(AVChannelLayout *channel_layout, enum AVChannelOrder order, int flags) { int allow_lossy = !(flags & AV_CHANNEL_LAYOUT_RETYPE_FLAG_LOSSLESS); int lossy; if (!av_channel_layout_check(channel_layout)) return AVERROR(EINVAL); if (flags & AV_CHANNEL_LAYOUT_RETYPE_FLAG_CANONICAL) order = canonical_order(channel_layout); if (channel_layout->order == order) return 0; switch (order) { case AV_CHANNEL_ORDER_UNSPEC: { int nb_channels = channel_layout->nb_channels; if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) { lossy = 0; for (int i = 0; i < nb_channels; i++) { if (channel_layout->u.map[i].id != AV_CHAN_UNKNOWN || channel_layout->u.map[i].name[0]) { lossy = 1; break; } } } else { lossy = 1; } if (!lossy || allow_lossy) { av_channel_layout_uninit(channel_layout); channel_layout->order = AV_CHANNEL_ORDER_UNSPEC; channel_layout->nb_channels = nb_channels; return lossy; } return AVERROR(ENOSYS); } case AV_CHANNEL_ORDER_NATIVE: if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) { int64_t mask = masked_description(channel_layout, 0); if (mask < 0) return AVERROR(ENOSYS); lossy = has_channel_names(channel_layout); if (!lossy || allow_lossy) { av_channel_layout_uninit(channel_layout); av_channel_layout_from_mask(channel_layout, mask); return lossy; } } return AVERROR(ENOSYS); case AV_CHANNEL_ORDER_CUSTOM: { AVChannelLayout custom = { 0 }; int ret = av_channel_layout_custom_init(&custom, channel_layout->nb_channels); if (ret < 0) return ret; if (channel_layout->order != AV_CHANNEL_ORDER_UNSPEC) for (int i = 0; i < channel_layout->nb_channels; i++) custom.u.map[i].id = av_channel_layout_channel_from_index(channel_layout, i); av_channel_layout_uninit(channel_layout); *channel_layout = custom; return 0; } case AV_CHANNEL_ORDER_AMBISONIC: if (channel_layout->order == AV_CHANNEL_ORDER_CUSTOM) { int64_t mask; int nb_channels = channel_layout->nb_channels; int order = ambisonic_order(channel_layout); if (order < 0) return AVERROR(ENOSYS); mask = masked_description(channel_layout, (order + 1) * (order + 1)); if (mask < 0) return AVERROR(ENOSYS); lossy = has_channel_names(channel_layout); if (!lossy || allow_lossy) { av_channel_layout_uninit(channel_layout); channel_layout->order = AV_CHANNEL_ORDER_AMBISONIC; channel_layout->nb_channels = nb_channels; channel_layout->u.mask = mask; return lossy; } } return AVERROR(ENOSYS); default: return AVERROR(EINVAL); } }