| /* |
| * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> |
| * |
| * 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 <stdint.h> |
| |
| #include "avstring.h" |
| #include "avutil.h" |
| #include "channel_layout.h" |
| #include "bprint.h" |
| #include "common.h" |
| |
| struct channel_name { |
| const char *name; |
| const char *description; |
| }; |
| |
| static const struct channel_name channel_names[] = { |
| [0] = { "FL", "front left" }, |
| [1] = { "FR", "front right" }, |
| [2] = { "FC", "front center" }, |
| [3] = { "LFE", "low frequency" }, |
| [4] = { "BL", "back left" }, |
| [5] = { "BR", "back right" }, |
| [6] = { "FLC", "front left-of-center" }, |
| [7] = { "FRC", "front right-of-center" }, |
| [8] = { "BC", "back center" }, |
| [9] = { "SL", "side left" }, |
| [10] = { "SR", "side right" }, |
| [11] = { "TC", "top center" }, |
| [12] = { "TFL", "top front left" }, |
| [13] = { "TFC", "top front center" }, |
| [14] = { "TFR", "top front right" }, |
| [15] = { "TBL", "top back left" }, |
| [16] = { "TBC", "top back center" }, |
| [17] = { "TBR", "top back right" }, |
| [29] = { "DL", "downmix left" }, |
| [30] = { "DR", "downmix right" }, |
| [31] = { "WL", "wide left" }, |
| [32] = { "WR", "wide right" }, |
| [33] = { "SDL", "surround direct left" }, |
| [34] = { "SDR", "surround direct right" }, |
| [35] = { "LFE2", "low frequency 2" }, |
| }; |
| |
| static const char *get_channel_name(int channel_id) |
| { |
| if (channel_id < 0 || channel_id >= FF_ARRAY_ELEMS(channel_names)) |
| return NULL; |
| return channel_names[channel_id].name; |
| } |
| |
| static const struct { |
| const char *name; |
| int nb_channels; |
| uint64_t layout; |
| } channel_layout_map[] = { |
| { "mono", 1, AV_CH_LAYOUT_MONO }, |
| { "stereo", 2, AV_CH_LAYOUT_STEREO }, |
| { "2.1", 3, AV_CH_LAYOUT_2POINT1 }, |
| { "3.0", 3, AV_CH_LAYOUT_SURROUND }, |
| { "3.0(back)", 3, AV_CH_LAYOUT_2_1 }, |
| { "4.0", 4, AV_CH_LAYOUT_4POINT0 }, |
| { "quad", 4, AV_CH_LAYOUT_QUAD }, |
| { "quad(side)", 4, AV_CH_LAYOUT_2_2 }, |
| { "3.1", 4, AV_CH_LAYOUT_3POINT1 }, |
| { "5.0", 5, AV_CH_LAYOUT_5POINT0_BACK }, |
| { "5.0(side)", 5, AV_CH_LAYOUT_5POINT0 }, |
| { "4.1", 5, AV_CH_LAYOUT_4POINT1 }, |
| { "5.1", 6, AV_CH_LAYOUT_5POINT1_BACK }, |
| { "5.1(side)", 6, AV_CH_LAYOUT_5POINT1 }, |
| { "6.0", 6, AV_CH_LAYOUT_6POINT0 }, |
| { "6.0(front)", 6, AV_CH_LAYOUT_6POINT0_FRONT }, |
| { "hexagonal", 6, AV_CH_LAYOUT_HEXAGONAL }, |
| { "6.1", 7, AV_CH_LAYOUT_6POINT1 }, |
| { "6.1(back)", 7, AV_CH_LAYOUT_6POINT1_BACK }, |
| { "6.1(front)", 7, AV_CH_LAYOUT_6POINT1_FRONT }, |
| { "7.0", 7, AV_CH_LAYOUT_7POINT0 }, |
| { "7.0(front)", 7, AV_CH_LAYOUT_7POINT0_FRONT }, |
| { "7.1", 8, AV_CH_LAYOUT_7POINT1 }, |
| { "7.1(wide)", 8, AV_CH_LAYOUT_7POINT1_WIDE_BACK }, |
| { "7.1(wide-side)", 8, AV_CH_LAYOUT_7POINT1_WIDE }, |
| { "octagonal", 8, AV_CH_LAYOUT_OCTAGONAL }, |
| { "hexadecagonal", 16, AV_CH_LAYOUT_HEXADECAGONAL }, |
| { "downmix", 2, AV_CH_LAYOUT_STEREO_DOWNMIX, }, |
| }; |
| |
| static uint64_t get_channel_layout_single(const char *name, int name_len) |
| { |
| int i; |
| char *end; |
| int64_t layout; |
| |
| for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) { |
| if (strlen(channel_layout_map[i].name) == name_len && |
| !memcmp(channel_layout_map[i].name, name, name_len)) |
| return channel_layout_map[i].layout; |
| } |
| for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) |
| if (channel_names[i].name && |
| strlen(channel_names[i].name) == name_len && |
| !memcmp(channel_names[i].name, name, name_len)) |
| return (int64_t)1 << i; |
| |
| errno = 0; |
| i = strtol(name, &end, 10); |
| |
| if (!errno && (end + 1 - name == name_len && *end == 'c')) |
| return av_get_default_channel_layout(i); |
| |
| errno = 0; |
| layout = strtoll(name, &end, 0); |
| if (!errno && end - name == name_len) |
| return FFMAX(layout, 0); |
| return 0; |
| } |
| |
| uint64_t av_get_channel_layout(const char *name) |
| { |
| const char *n, *e; |
| const char *name_end = name + strlen(name); |
| int64_t layout = 0, layout_single; |
| |
| for (n = name; n < name_end; n = e + 1) { |
| for (e = n; e < name_end && *e != '+' && *e != '|'; e++); |
| layout_single = get_channel_layout_single(n, e - n); |
| if (!layout_single) |
| return 0; |
| layout |= layout_single; |
| } |
| return layout; |
| } |
| |
| int av_get_extended_channel_layout(const char *name, uint64_t* channel_layout, int* nb_channels) |
| { |
| int nb = 0; |
| char *end; |
| uint64_t layout = av_get_channel_layout(name); |
| |
| if (layout) { |
| *channel_layout = layout; |
| *nb_channels = av_get_channel_layout_nb_channels(layout); |
| return 0; |
| } |
| |
| nb = strtol(name, &end, 10); |
| if (!errno && *end == 'C' && *(end + 1) == '\0' && nb > 0 && nb < 64) { |
| *channel_layout = 0; |
| *nb_channels = nb; |
| return 0; |
| } |
| |
| return AVERROR(EINVAL); |
| } |
| |
| void av_bprint_channel_layout(struct AVBPrint *bp, |
| int nb_channels, uint64_t channel_layout) |
| { |
| int i; |
| |
| if (nb_channels <= 0) |
| nb_channels = av_get_channel_layout_nb_channels(channel_layout); |
| |
| for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) |
| if (nb_channels == channel_layout_map[i].nb_channels && |
| channel_layout == channel_layout_map[i].layout) { |
| av_bprintf(bp, "%s", channel_layout_map[i].name); |
| return; |
| } |
| |
| av_bprintf(bp, "%d channels", nb_channels); |
| if (channel_layout) { |
| int i, ch; |
| av_bprintf(bp, " ("); |
| for (i = 0, ch = 0; i < 64; i++) { |
| if ((channel_layout & (UINT64_C(1) << i))) { |
| const char *name = get_channel_name(i); |
| if (name) { |
| if (ch > 0) |
| av_bprintf(bp, "+"); |
| av_bprintf(bp, "%s", name); |
| } |
| ch++; |
| } |
| } |
| av_bprintf(bp, ")"); |
| } |
| } |
| |
| void av_get_channel_layout_string(char *buf, int buf_size, |
| int nb_channels, uint64_t channel_layout) |
| { |
| AVBPrint bp; |
| |
| av_bprint_init_for_buffer(&bp, buf, buf_size); |
| av_bprint_channel_layout(&bp, nb_channels, channel_layout); |
| } |
| |
| int av_get_channel_layout_nb_channels(uint64_t channel_layout) |
| { |
| return av_popcount64(channel_layout); |
| } |
| |
| int64_t av_get_default_channel_layout(int nb_channels) { |
| int i; |
| for (i = 0; i < FF_ARRAY_ELEMS(channel_layout_map); i++) |
| if (nb_channels == channel_layout_map[i].nb_channels) |
| return channel_layout_map[i].layout; |
| return 0; |
| } |
| |
| int av_get_channel_layout_channel_index(uint64_t channel_layout, |
| uint64_t channel) |
| { |
| if (!(channel_layout & channel) || |
| av_get_channel_layout_nb_channels(channel) != 1) |
| return AVERROR(EINVAL); |
| channel_layout &= channel - 1; |
| return av_get_channel_layout_nb_channels(channel_layout); |
| } |
| |
| const char *av_get_channel_name(uint64_t channel) |
| { |
| int i; |
| if (av_get_channel_layout_nb_channels(channel) != 1) |
| return NULL; |
| for (i = 0; i < 64; i++) |
| if ((1ULL<<i) & channel) |
| return get_channel_name(i); |
| return NULL; |
| } |
| |
| const char *av_get_channel_description(uint64_t channel) |
| { |
| int i; |
| if (av_get_channel_layout_nb_channels(channel) != 1) |
| return NULL; |
| for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) |
| if ((1ULL<<i) & channel) |
| return channel_names[i].description; |
| return NULL; |
| } |
| |
| uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index) |
| { |
| int i; |
| |
| if (av_get_channel_layout_nb_channels(channel_layout) <= index) |
| return 0; |
| |
| for (i = 0; i < 64; i++) { |
| if ((1ULL << i) & channel_layout && !index--) |
| return 1ULL << i; |
| } |
| return 0; |
| } |
| |
| int av_get_standard_channel_layout(unsigned index, uint64_t *layout, |
| const char **name) |
| { |
| if (index >= FF_ARRAY_ELEMS(channel_layout_map)) |
| return AVERROR_EOF; |
| if (layout) *layout = channel_layout_map[index].layout; |
| if (name) *name = channel_layout_map[index].name; |
| return 0; |
| } |
