Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1006 insertions, 0 deletions

diff --git a/media/ffvpx/libavutil/channel_layout.c b/media/ffvpx/libavutil/channel_layout.c
new file mode 100644
index 0000000000..e2f7512254
--- /dev/null
+++ b/media/ffvpx/libavutil/channel_layout.c
@@ -0,0 +1,1006 @@
+/*
+ * 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 <stdlib.h>
+#include <string.h>
+
+#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"    },
+};
+
+static const char *get_channel_name(enum AVChannel channel_id)
+{
+    if ((unsigned) channel_id >= FF_ARRAY_ELEMS(channel_names) ||
+        !channel_names[channel_id].name)
+        return NULL;
+    return channel_names[channel_id].name;
+}
+
+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);
+
+    return bp.len;
+}
+
+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);
+
+    return bp.len;
+}
+
+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       },
+    { "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        },
+    { "7.1(top)",       AV_CHANNEL_LAYOUT_7POINT1_TOP_BACK    },
+    { "octagonal",      AV_CHANNEL_LAYOUT_OCTAGONAL           },
+    { "cube",           AV_CHANNEL_LAYOUT_CUBE                },
+    { "hexadecagonal",  AV_CHANNEL_LAYOUT_HEXADECAGONAL       },
+    { "downmix",        AV_CHANNEL_LAYOUT_STEREO_DOWNMIX,     },
+    { "22.2",           AV_CHANNEL_LAYOUT_22POINT2,           },
+};
+
+#if FF_API_OLD_CHANNEL_LAYOUT
+FF_DISABLE_DEPRECATION_WARNINGS
+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.u.mask;
+    }
+    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].layout.nb_channels &&
+            channel_layout == channel_layout_map[i].layout.u.mask) {
+            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].layout.nb_channels)
+            return channel_layout_map[i].layout.u.mask;
+    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.u.mask;
+    if (name)   *name   = channel_layout_map[index].name;
+    return 0;
+}
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+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;
+}
+
+int av_channel_layout_from_string(AVChannelLayout *channel_layout,
+                                  const char *str)
+{
+    int i;
+    int channels = 0, nb_channels = 0, native = 1;
+    enum AVChannel highest_channel = AV_CHAN_NONE;
+    const char *dup;
+    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;
+        }
+    }
+
+    /* 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(&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 */
+    av_sscanf(str, "%d channels (%[^)]", &nb_channels, chlist);
+    end = strchr(str, ')');
+
+    dup = chlist;
+    while (*dup) {
+        char *channel, *chname;
+        int ret = av_opt_get_key_value(&dup, "@", "+", AV_OPT_FLAG_IMPLICIT_KEY, &channel, &chname);
+        if (ret < 0) {
+            av_free(chlist);
+            return ret;
+        }
+        if (*dup)
+            dup++; // skip separator
+        if (channel && !*channel)
+            av_freep(&channel);
+        for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
+            if (channel_names[i].name && !strcmp(channel ? channel : chname, channel_names[i].name)) {
+                if (channel || i < highest_channel || mask & (1ULL << i))
+                    native = 0; // Not a native layout, use a custom one
+                highest_channel = i;
+                mask |= 1ULL << i;
+                break;
+            }
+        }
+
+        if (!channel && i >= FF_ARRAY_ELEMS(channel_names)) {
+            char *endptr = chname;
+            enum AVChannel id = AV_CHAN_NONE;
+
+            if (!strncmp(chname, "USR", 3)) {
+                const char *p = chname + 3;
+                id = strtol(p, &endptr, 0);
+            }
+            if (id < 0 || *endptr) {
+                native = 0; // Unknown channel name
+                channels = 0;
+                mask = 0;
+                av_free(chname);
+                break;
+            }
+            if (id > 63)
+                native = 0; // Not a native layout, use a custom one
+            else {
+                if (id < highest_channel || mask & (1ULL << id))
+                    native = 0; // Not a native layout, use a custom one
+                highest_channel = id;
+                mask |= 1ULL << id;
+            }
+        }
+        channels++;
+        av_free(channel);
+        av_free(chname);
+    }
+
+    if (mask && native) {
+        av_free(chlist);
+        if (nb_channels && ((nb_channels != channels) || (!end || *++end)))
+            return AVERROR(EINVAL);
+        av_channel_layout_from_mask(channel_layout, mask);
+        return 0;
+    }
+
+    /* custom layout of channel names */
+    if (channels && !native) {
+        int idx = 0;
+
+        if (nb_channels && ((nb_channels != channels) || (!end || *++end))) {
+            av_free(chlist);
+            return AVERROR(EINVAL);
+        }
+
+        channel_layout->u.map = av_calloc(channels, sizeof(*channel_layout->u.map));
+        if (!channel_layout->u.map) {
+            av_free(chlist);
+            return AVERROR(ENOMEM);
+        }
+
+        channel_layout->order = AV_CHANNEL_ORDER_CUSTOM;
+        channel_layout->nb_channels = channels;
+
+        dup = chlist;
+        while (*dup) {
+            char *channel, *chname;
+            int ret = av_opt_get_key_value(&dup, "@", "+", AV_OPT_FLAG_IMPLICIT_KEY, &channel, &chname);
+            if (ret < 0) {
+                av_freep(&channel_layout->u.map);
+                av_free(chlist);
+                return ret;
+            }
+            if (*dup)
+                dup++; // skip separator
+            for (i = 0; i < FF_ARRAY_ELEMS(channel_names); i++) {
+                if (channel_names[i].name && !strcmp(channel ? channel : chname, channel_names[i].name)) {
+                    channel_layout->u.map[idx].id = i;
+                    if (channel)
+                        av_strlcpy(channel_layout->u.map[idx].name, chname, sizeof(channel_layout->u.map[idx].name));
+                    idx++;
+                    break;
+                }
+            }
+            if (i >= FF_ARRAY_ELEMS(channel_names)) {
+                const char *p = (channel ? channel : chname) + 3;
+                channel_layout->u.map[idx].id = strtol(p, NULL, 0);
+                if (channel)
+                    av_strlcpy(channel_layout->u.map[idx].name, chname, sizeof(channel_layout->u.map[idx].name));
+                idx++;
+            }
+            av_free(channel);
+            av_free(chname);
+        }
+        av_free(chlist);
+
+        return 0;
+    }
+    av_freep(&chlist);
+
+    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;
+}
+
+/**
+ * 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;
+}
+
+/**
+ * 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 {
+            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) {
+            int res = try_describe_ambisonic(bp, channel_layout);
+            if (res >= 0)
+                return 0;
+        }
+        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;
+
+    return bp.len;
+}
+
+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;
+}