+static av_cold int set_channel_info(AC3EncodeContext *s, int channels,
+ int64_t *channel_layout)
+{
+ int ch_layout;
+
+ if (channels < 1 || channels > AC3_MAX_CHANNELS)
+ return -1;
+ if ((uint64_t)*channel_layout > 0x7FF)
+ return -1;
+ ch_layout = *channel_layout;
+ if (!ch_layout)
+ ch_layout = avcodec_guess_channel_layout(channels, CODEC_ID_AC3, NULL);
+ if (avcodec_channel_layout_num_channels(ch_layout) != channels)
+ return -1;
+
+ s->lfe = !!(ch_layout & CH_LOW_FREQUENCY);
+ s->nb_all_channels = channels;
+ s->nb_channels = channels - s->lfe;
+ s->lfe_channel = s->lfe ? s->nb_channels : -1;
+ if (s->lfe)
+ ch_layout -= CH_LOW_FREQUENCY;
+
+ switch (ch_layout) {
+ case CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;
+ case CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
+ case CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
+ case CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
+ case CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
+ case CH_LAYOUT_QUAD:
+ case CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
+ case CH_LAYOUT_5POINT0:
+ case CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
+ default:
+ return -1;
+ }
+
+ s->channel_map = ff_ac3_enc_channel_map[s->channel_mode][s->lfe];
+ *channel_layout = ch_layout;
+ if (s->lfe)
+ *channel_layout |= CH_LOW_FREQUENCY;
+
+ return 0;
+}
+
+static av_cold int AC3_encode_init(AVCodecContext *avctx)