static av_cold int channelmap_init(AVFilterContext *ctx) { ChannelMapContext *s = ctx->priv; int ret; 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); 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, separator, 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, separator)) { 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, separator, 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, separator) < 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, separator, 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, separator) < 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; }