#include "vgmstream.h" #include "mixing.h" #include "plugins.h" #include #include /** * Mixing lets vgmstream modify the resulting sample buffer before final output. * This can be implemented in a number of ways but it's done like it is considering * overall simplicity in coding, usage and performance (main complexity is allowing * down/upmixing). Code is mostly independent with some hooks in the main vgmstream * code. * * It works using two buffers: * - outbuf: plugin's pcm16 buffer, at least input_channels*sample_count * - mixbuf: internal's pcmfloat buffer, at least mixing_channels*sample_count * outbuf starts with decoded samples of vgmstream->channel size. This unsures that * if no mixing is done (most common case) we can skip copying samples between buffers. * Resulting outbuf after mixing has samples for ->output_channels (plus garbage). * - output_channels is the resulting total channels (that may be less/more/equal) * - input_channels is normally ->channels or ->output_channels when it's higher * * First, a meta (ex. TXTP) or plugin may add mixing commands through the API, * validated so non-sensical mixes are ignored (to ensure mixing code doesn't * have to recheck every time). Then, before starting to decode mixing must be * manually activated, because plugins need to be ready for possibly different * input/output channels. API could be improved but this way we can avoid having * to update all plugins, while allowing internal setup and layer/segment mixing * (may change in the future for simpler usage). * * Then after decoding normally, vgmstream applies mixing internally: * - detect if mixing is active and needs to be done at this point (some effects * like fades only apply after certain time) and skip otherwise. * - copy outbuf to mixbuf, as using a float buffer to increase accuracy (most ops * apply float volumes) and slightly improve performance (avoids doing * int16-to-float casts per mix, as it's not free) * - apply all mixes on mixbuf * - copy mixbuf to outbuf * segmented/layered layouts handle mixing on their own. * * Mixing is tuned for most common case (no mix except fade-out at the end) and is * fast enough but not super-optimized yet, there is some penalty the more effects * are applied. Maybe could add extra sub-ops to avoid ifs and dumb values (volume=0.0 * could simply use a clear op), only use mixbuf if necessary (swap can be done without * mixbuf if it goes first) or add function pointer indexes but isn't too important. * Operations are applied once per "step" with 1 sample from all channels to simplify code * (and maybe improve memory cache?), though maybe it should call one function per operation. */ #define VGMSTREAM_MAX_MIXING 512 #define MIXING_PI 3.14159265358979323846f /* mixing info */ typedef enum { MIX_SWAP, MIX_ADD, MIX_VOLUME, MIX_LIMIT, MIX_UPMIX, MIX_DOWNMIX, MIX_KILLMIX, MIX_FADE } mix_command_t; typedef struct { mix_command_t command; /* common */ int ch_dst; int ch_src; float vol; /* fade envelope */ float vol_start; /* volume from pre to start */ float vol_end; /* volume from end to post */ char shape; /* curve type */ int32_t time_pre; /* position before time_start where vol_start applies (-1 = beginning) */ int32_t time_start; /* fade start position where vol changes from vol_start to vol_end */ int32_t time_end; /* fade end position where vol changes from vol_start to vol_end */ int32_t time_post; /* position after time_end where vol_end applies (-1 = end) */ } mix_command_data; typedef struct { int mixing_channels; /* max channels needed to mix */ int output_channels; /* resulting channels after mixing */ int mixing_on; /* mixing allowed */ int mixing_count; /* mixing number */ size_t mixing_size; /* mixing max */ mix_command_data mixing_chain[VGMSTREAM_MAX_MIXING]; /* effects to apply (could be alloc'ed but to simplify...) */ float* mixbuf; /* internal mixing buffer */ } mixing_data; /* ******************************************************************* */ static int is_active(mixing_data *data, int32_t current_start, int32_t current_end) { int i; int32_t fade_start, fade_end; for (i = 0; i < data->mixing_count; i++) { mix_command_data *mix = &data->mixing_chain[i]; if (mix->command != MIX_FADE) return 1; /* has non-fades = active */ /* check is current range falls within a fade * (assuming fades were already optimized on add) */ fade_start = mix->time_pre < 0 ? 0 : mix->time_pre; fade_end = mix->time_post < 0 ? INT_MAX : mix->time_post; if (current_start < fade_end && current_end > fade_start) return 1; } return 0; } static int32_t get_current_pos(VGMSTREAM* vgmstream, int32_t sample_count) { int32_t current_pos; if (vgmstream->loop_flag && vgmstream->loop_count > 0) { int loop_pre = vgmstream->loop_start_sample; /* samples before looping */ int loop_into = (vgmstream->current_sample - vgmstream->loop_start_sample); /* samples after loop */ int loop_samples = (vgmstream->loop_end_sample - vgmstream->loop_start_sample); /* looped section */ current_pos = loop_pre + (loop_samples * vgmstream->loop_count) + loop_into - sample_count; } else { current_pos = (vgmstream->current_sample - sample_count); } return current_pos; } static float get_fade_gain_curve(char shape, float index) { float gain; /* don't bother doing calcs near 0.0/1.0 */ if (index <= 0.0001f || index >= 0.9999f) { return index; } //todo optimizations: interleave calcs, maybe use cosf, powf, etc? (with extra defines) /* (curve math mostly from SoX/FFmpeg) */ switch(shape) { /* 2.5f in L/E 'pow' is the attenuation factor, where 5.0 (100db) is common but a bit fast * (alt calculations with 'exp' from FFmpeg use (factor)*ln(0.1) = -NN.N... */ case 'E': /* exponential (for fade-outs, closer to natural decay of sound) */ //gain = pow(0.1f, (1.0f - index) * 2.5f); gain = exp(-5.75646273248511f * (1.0f - index)); break; case 'L': /* logarithmic (inverse of the above, maybe for crossfades) */ //gain = 1 - pow(0.1f, (index) * 2.5f); gain = 1 - exp(-5.75646273248511f * (index)); break; case 'H': /* raised sine wave or cosine wave (for more musical crossfades) */ gain = (1.0f - cos(index * MIXING_PI)) / 2.0f; break; case 'Q': /* quarter of sine wave (for musical fades) */ gain = sin(index * MIXING_PI / 2.0f); break; case 'p': /* parabola (maybe for crossfades) */ gain = 1.0f - sqrt(1.0f - index); break; case 'P': /* inverted parabola (maybe for fades) */ gain = (1.0f - (1.0f - index) * (1.0f - index)); break; case 'T': /* triangular/linear (simpler/sharper fades) */ default: gain = index; break; } return gain; } static int get_fade_gain(mix_command_data *mix, float *out_cur_vol, int32_t current_subpos) { float cur_vol = 0.0f; if ((current_subpos >= mix->time_pre || mix->time_pre < 0) && current_subpos < mix->time_start) { cur_vol = mix->vol_start; /* before */ } else if (current_subpos >= mix->time_end && (current_subpos < mix->time_post || mix->time_post < 0)) { cur_vol = mix->vol_end; /* after */ } else if (current_subpos >= mix->time_start && current_subpos < mix->time_end) { /* in between */ float range_vol, range_dur, range_idx, index, gain; if (mix->vol_start < mix->vol_end) { /* fade in */ range_vol = mix->vol_end - mix->vol_start; range_dur = mix->time_end - mix->time_start; range_idx = current_subpos - mix->time_start; index = range_idx / range_dur; } else { /* fade out */ range_vol = mix->vol_end - mix->vol_start; range_dur = mix->time_end - mix->time_start; range_idx = mix->time_end - current_subpos; index = range_idx / range_dur; } /* Fading is done like this: * - find current position within fade duration * - get linear % (or rather, index from 0.0 .. 1.0) of duration * - apply shape to % (from linear fade to curved fade) * - get final volume for that point * * Roughly speaking some curve shapes are better for fades (decay rate is more natural * sounding in that highest to mid/low happens faster but low to lowest takes more time, * kinda like a gunshot or bell), and others for crossfades (decay of fade-in + fade-out * is adjusted so that added volume level stays constant-ish). * * As curves can fade in two ways ('normal' and curving 'the other way'), they are adjusted * to get 'normal' shape on both fades (by reversing index and making 1 - gain), thus some * curves are complementary (exponential fade-in ~= logarithmic fade-out); the following * are described taking fade-in = normal. */ gain = get_fade_gain_curve(mix->shape, index); if (mix->vol_start < mix->vol_end) { /* fade in */ cur_vol = mix->vol_start + range_vol * gain; } else { /* fade out */ cur_vol = mix->vol_end - range_vol * gain; //mix->vol_start - range_vol * (1 - gain); } } else { /* fade is outside reach */ goto fail; } *out_cur_vol = cur_vol; return 1; fail: return 0; } void mix_vgmstream(sample_t *outbuf, int32_t sample_count, VGMSTREAM* vgmstream) { mixing_data *data = vgmstream->mixing_data; int ch, s, m, ok; int32_t current_pos, current_subpos; float temp_f, temp_min, temp_max, cur_vol = 0.0f; float *temp_mixbuf; sample_t *temp_outbuf; const float limiter_max = 32767.0f; const float limiter_min = -32768.0f; /* no support or not need to apply */ if (!data || !data->mixing_on || data->mixing_count == 0) return; /* try to skip if no ops apply (for example if fade set but does nothing yet) */ current_pos = get_current_pos(vgmstream, sample_count); if (!is_active(data, current_pos, current_pos + sample_count)) return; /* use advancing buffer pointers to simplify logic */ temp_mixbuf = data->mixbuf; temp_outbuf = outbuf; current_subpos = current_pos; /* apply mixes in order per channel */ for (s = 0; s < sample_count; s++) { /* reset after new sample 'step'*/ float *stpbuf = temp_mixbuf; int step_channels = vgmstream->channels; for (ch = 0; ch < step_channels; ch++) { stpbuf[ch] = temp_outbuf[ch]; /* copy current 'lane' */ } for (m = 0; m < data->mixing_count; m++) { mix_command_data *mix = &data->mixing_chain[m]; /* mixing ops are designed to apply in order, all channels per 1 sample 'step'. Since some ops change * total channels, channel number meaning varies as ops move them around, ex: * - 4ch w/ "1-2,2+3" = ch1<>ch3, ch2(old ch1)+ch3 = 4ch: ch2 ch1+ch3 ch3 ch4 * - 4ch w/ "2+3,1-2" = ch2+ch3, ch1<>ch2(modified) = 4ch: ch2+ch3 ch1 ch3 ch4 * - 2ch w/ "1+2,1u" = ch1+ch2, ch1(add and push rest) = 3ch: ch1' ch1+ch2 ch2 * - 2ch w/ "1u,1+2" = ch1(add and push rest) = 3ch: ch1'+ch1 ch1 ch2 * - 2ch w/ "1-2,1d" = ch1<>ch2, ch1(drop and move ch2(old ch1) to ch1) = ch1 * - 2ch w/ "1d,1-2" = ch1(drop and pull rest), ch1(do nothing, ch2 doesn't exist now) = ch2 */ switch(mix->command) { case MIX_SWAP: temp_f = stpbuf[mix->ch_dst]; stpbuf[mix->ch_dst] = stpbuf[mix->ch_src]; stpbuf[mix->ch_src] = temp_f; break; case MIX_ADD: stpbuf[mix->ch_dst] = stpbuf[mix->ch_dst] + stpbuf[mix->ch_src] * mix->vol; break; case MIX_VOLUME: if (mix->ch_dst < 0) { for (ch = 0; ch < step_channels; ch++) { stpbuf[ch] = stpbuf[ch] * mix->vol; } } else { stpbuf[mix->ch_dst] = stpbuf[mix->ch_dst] * mix->vol; } break; case MIX_LIMIT: temp_max = limiter_max * mix->vol; temp_min = limiter_min * mix->vol; if (mix->ch_dst < 0) { for (ch = 0; ch < step_channels; ch++) { if (stpbuf[ch] > temp_max) stpbuf[ch] = temp_max; else if (stpbuf[ch] < temp_min) stpbuf[ch] = temp_min; } } else { if (stpbuf[mix->ch_dst] > temp_max) stpbuf[mix->ch_dst] = temp_max; else if (stpbuf[mix->ch_dst] < temp_min) stpbuf[mix->ch_dst] = temp_min; } break; case MIX_UPMIX: step_channels += 1; for (ch = step_channels - 1; ch > mix->ch_dst; ch--) { stpbuf[ch] = stpbuf[ch-1]; /* 'push' channels forward (or pull backwards) */ } stpbuf[mix->ch_dst] = 0; /* inserted as silent */ break; case MIX_DOWNMIX: step_channels -= 1; for (ch = mix->ch_dst; ch < step_channels; ch++) { stpbuf[ch] = stpbuf[ch+1]; /* 'pull' channels back */ } break; case MIX_KILLMIX: step_channels = mix->ch_dst; /* clamp channels */ break; case MIX_FADE: ok = get_fade_gain(mix, &cur_vol, current_subpos); if (!ok) { break; /* fade doesn't apply right now */ } if (mix->ch_dst < 0) { for (ch = 0; ch < step_channels; ch++) { stpbuf[ch] = stpbuf[ch] * cur_vol; } } else { stpbuf[mix->ch_dst] = stpbuf[mix->ch_dst] * cur_vol; } break; default: break; } } current_subpos++; temp_mixbuf += step_channels; temp_outbuf += vgmstream->channels; } /* copy resulting mix to output */ for (s = 0; s < sample_count * data->output_channels; s++) { /* when casting float to int, value is simply truncated: * - (int)1.7 = 1, (int)-1.7 = -1 * alts for more accurate rounding could be: * - (int)floor(f) * - (int)(f < 0 ? f - 0.5f : f + 0.5f) * - (((int) (f1 + 32768.5)) - 32768) * - etc * but since +-1 isn't really audible we'll just cast as it's the fastest */ outbuf[s] = clamp16( (int32_t)data->mixbuf[s] ); } } /* ******************************************************************* */ void mixing_init(VGMSTREAM* vgmstream) { mixing_data *data = calloc(1, sizeof(mixing_data)); if (!data) goto fail; data->mixing_size = VGMSTREAM_MAX_MIXING; /* fixed array for now */ data->mixing_channels = vgmstream->channels; data->output_channels = vgmstream->channels; vgmstream->mixing_data = data; return; fail: free(data); return; } void mixing_close(VGMSTREAM* vgmstream) { mixing_data *data = NULL; if (!vgmstream) return; data = vgmstream->mixing_data; if (!data) return; free(data->mixbuf); free(data); } void mixing_update_channel(VGMSTREAM* vgmstream) { mixing_data *data = vgmstream->mixing_data; if (!data) return; /* lame hack for dual stereo, but dual stereo is pretty hack-ish to begin with */ data->mixing_channels++; data->output_channels++; } /* ******************************************************************* */ static int add_mixing(VGMSTREAM* vgmstream, mix_command_data *mix) { mixing_data *data = vgmstream->mixing_data; if (!data) return 0; if (data->mixing_on) { VGM_LOG("MIX: ignoring new mixes when mixing active\n"); return 0; /* to avoid down/upmixing after activation */ } if (data->mixing_count + 1 > data->mixing_size) { VGM_LOG("MIX: too many mixes\n"); return 0; } data->mixing_chain[data->mixing_count] = *mix; /* memcpy */ data->mixing_count++; //;VGM_LOG("MIX: total %i\n", data->mixing_count); return 1; } void mixing_push_swap(VGMSTREAM* vgmstream, int ch_dst, int ch_src) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; if (ch_dst < 0 || ch_src < 0 || ch_dst == ch_src) return; if (!data || ch_dst >= data->output_channels || ch_src >= data->output_channels) return; mix.command = MIX_SWAP; mix.ch_dst = ch_dst; mix.ch_src = ch_src; add_mixing(vgmstream, &mix); } void mixing_push_add(VGMSTREAM* vgmstream, int ch_dst, int ch_src, double volume) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; if (!data) return; //if (volume < 0.0) return; /* negative volume inverts the waveform */ if (volume == 0.0) return; /* ch_src becomes silent and nothing is added */ if (ch_dst < 0 || ch_src < 0) return; if (!data || ch_dst >= data->output_channels || ch_src >= data->output_channels) return; mix.command = MIX_ADD; //if (volume == 1.0) MIX_ADD_COPY /* could simplify */ mix.ch_dst = ch_dst; mix.ch_src = ch_src; mix.vol = volume; //;VGM_LOG("MIX: add %i+%i*%f\n", ch_dst,ch_src,volume); add_mixing(vgmstream, &mix); } void mixing_push_volume(VGMSTREAM* vgmstream, int ch_dst, double volume) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; //if (ch_dst < 0) return; /* means all channels */ //if (volume < 0.0) return; /* negative volume inverts the waveform */ if (volume == 1.0) return; /* no change */ if (!data || ch_dst >= data->output_channels) return; mix.command = MIX_VOLUME; //if (volume == 0.0) MIX_VOLUME0 /* could simplify */ mix.ch_dst = ch_dst; mix.vol = volume; //;VGM_LOG("MIX: volume %i*%f\n", ch_dst,volume); add_mixing(vgmstream, &mix); } void mixing_push_limit(VGMSTREAM* vgmstream, int ch_dst, double volume) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; //if (ch_dst < 0) return; /* means all channels */ if (volume < 0.0) return; if (volume == 1.0) return; /* no actual difference */ if (!data || ch_dst >= data->output_channels) return; //if (volume == 0.0) return; /* dumb but whatevs */ mix.command = MIX_LIMIT; mix.ch_dst = ch_dst; mix.vol = volume; add_mixing(vgmstream, &mix); } void mixing_push_upmix(VGMSTREAM* vgmstream, int ch_dst) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; int ok; if (ch_dst < 0) return; if (!data || ch_dst > data->output_channels || data->output_channels +1 > VGMSTREAM_MAX_CHANNELS) return; /* dst can be == output_channels here, since we are inserting */ mix.command = MIX_UPMIX; mix.ch_dst = ch_dst; ok = add_mixing(vgmstream, &mix); if (ok) { data->output_channels += 1; if (data->mixing_channels < data->output_channels) data->mixing_channels = data->output_channels; } } void mixing_push_downmix(VGMSTREAM* vgmstream, int ch_dst) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; int ok; if (ch_dst < 0) return; if (!data || ch_dst >= data->output_channels || data->output_channels - 1 < 1) return; mix.command = MIX_DOWNMIX; mix.ch_dst = ch_dst; ok = add_mixing(vgmstream, &mix); if (ok) { data->output_channels -= 1; } } void mixing_push_killmix(VGMSTREAM* vgmstream, int ch_dst) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; int ok; if (ch_dst <= 0) return; /* can't kill from first channel */ if (!data || ch_dst >= data->output_channels) return; mix.command = MIX_KILLMIX; mix.ch_dst = ch_dst; //;VGM_LOG("MIX: killmix %i\n", ch_dst); ok = add_mixing(vgmstream, &mix); if (ok) { data->output_channels = ch_dst; /* clamp channels */ } } static mix_command_data* get_last_fade(mixing_data *data, int target_channel) { int i; for (i = data->mixing_count; i > 0; i--) { mix_command_data *mix = &data->mixing_chain[i-1]; if (mix->command != MIX_FADE) continue; if (mix->ch_dst == target_channel) return mix; } return NULL; } void mixing_push_fade(VGMSTREAM* vgmstream, int ch_dst, double vol_start, double vol_end, char shape, int32_t time_pre, int32_t time_start, int32_t time_end, int32_t time_post) { mixing_data *data = vgmstream->mixing_data; mix_command_data mix = {0}; mix_command_data *mix_prev; //if (ch_dst < 0) return; /* means all channels */ if (!data || ch_dst >= data->output_channels) return; if (time_pre > time_start || time_start > time_end || (time_post >= 0 && time_end > time_post)) return; if (time_start < 0 || time_end < 0) return; //if (time_pre < 0 || time_post < 0) return; /* special meaning of file start/end */ //if (vol_start == vol_end) /* weird but let in case of being used to cancel others fades... maybe? */ if (shape == '{' || shape == '}') shape = 'E'; if (shape == '(' || shape == ')') shape = 'H'; mix.command = MIX_FADE; mix.ch_dst = ch_dst; mix.vol_start = vol_start; mix.vol_end = vol_end; mix.shape = shape; mix.time_pre = time_pre; mix.time_start = time_start; mix.time_end = time_end; mix.time_post = time_post; /* cancel fades and optimize a bit when using negative pre/post: * - fades work like this: * <----------|----------|----------> * pre1 start1 end1 post1 * - when pre and post are set nothing is done (fade is exact and multiple fades may overlap) * - when previous fade's post or current fade's pre are negative (meaning file end/start) * they should cancel each other (to allow chaning fade-in + fade-out + fade-in + etc): * <----------|----------|----------| |----------|----------|----------> * pre1 start1 end1 post1 pre2 start2 end2 post2 * - other cases (previous fade is actually after/in-between current fade) are ignored * as they're uncommon and hard to optimize * fades cancel fades of the same channel, and 'all channel' (-1) fades also cancel 'all channels' */ mix_prev = get_last_fade(data, mix.ch_dst); if (mix_prev == NULL) { if (vol_start == 1.0 && time_pre < 0) time_pre = time_start; /* fade-out helds default volume before fade start can be clamped */ if (vol_end == 1.0 && time_post < 0) time_post = time_end; /* fade-in helds default volume after fade end can be clamped */ } else if (mix_prev->time_post < 0 || mix.time_pre < 0) { int is_prev = 1; if ((mix_prev->time_end > mix.time_start) || (mix_prev->time_post >= 0 && mix_prev->time_post > mix.time_start) || (mix.time_pre >= 0 && mix.time_pre < mix_prev->time_end)) is_prev = 0; if (is_prev) { /* change negative values to actual points */ if (mix_prev->time_post < 0 && mix_prev->time_post < 0) { mix_prev->time_post = mix_prev->time_end; mix.time_pre = mix_prev->time_post; } if (mix_prev->time_post >= 0 && mix.time_pre < 0) { mix.time_pre = mix_prev->time_post; } else if (mix_prev->time_post < 0 && mix.time_pre >= 0) { mix_prev->time_post = mix.time_pre; } /* else: both define start/ends, do nothing */ } /* should only modify prev if add_mixing but meh */ } //;VGM_LOG("MIX: fade %i^%f~%f=%c@%i~%i~%i~%i\n", ch_dst, vol_start, vol_end, shape, time_pre, time_start, time_end, time_post); add_mixing(vgmstream, &mix); } /* ******************************************************************* */ void mixing_macro_volume(VGMSTREAM* vgmstream, double volume, uint32_t mask) { mixing_data *data = vgmstream->mixing_data; int ch; if (!data) return; if (mask == 0) { mixing_push_volume(vgmstream, -1, volume); return; } for (ch = 0; ch < data->output_channels; ch++) { if (!((mask >> ch) & 1)) continue; mixing_push_volume(vgmstream, ch, volume); } } void mixing_macro_track(VGMSTREAM* vgmstream, uint32_t mask) { mixing_data *data = vgmstream->mixing_data; int ch; if (!data) return; if (mask == 0) { return; } /* reverse remove all channels (easier this way as when removing channels numbers change) */ for (ch = data->output_channels - 1; ch >= 0; ch--) { if ((mask >> ch) & 1) continue; mixing_push_downmix(vgmstream, ch); } } void mixing_macro_layer(VGMSTREAM* vgmstream, int max, uint32_t mask, char mode) { mixing_data *data = vgmstream->mixing_data; int current, ch, output_channels, selected_channels; if (!data) return; if (max <= 0 || data->output_channels <= max) return; /* set all channels (non-existant channels will be ignored) */ if (mask == 0) { mask = ~mask; } /* save before adding fake channels */ output_channels = data->output_channels; /* count possibly set channels */ selected_channels = 0; for (ch = 0; ch < output_channels; ch++) { selected_channels += (mask >> ch) & 1; } /* make N fake channels at the beginning for easier calcs */ for (ch = 0; ch < max; ch++) { mixing_push_upmix(vgmstream, 0); } /* add all layers in this order: ch0: 0, 0+N, 0+N*2 ... / ch1: 1, 1+N ... */ current = 0; for (ch = 0; ch < output_channels; ch++) { double volume = 1.0; if (!((mask >> ch) & 1)) continue; /* mode 'v': same volume for all layers (for layered vocals) */ /* mode 'b': volume adjusted depending on layers (for layered bgm) */ /* mode 'e': volume adjusted equally for all layers (for generic downmixing) */ if (mode == 'b' && ch < max) { /* reduce a bit main channels (see below) */ int channel_mixes = selected_channels / max; if (current < selected_channels % (channel_mixes * max)) /* may be simplified? */ channel_mixes += 1; channel_mixes -= 1; /* better formula? */ if (channel_mixes <= 0) /* ??? */ channel_mixes = 1; volume = 1 / sqrt(channel_mixes); } if ((mode == 'b' && ch >= max) || (mode == 'e')) { /* find how many will be mixed in current channel (earlier channels receive more * mixes than later ones, ex: selected 8ch + max 3ch: ch0=0+3+6, ch1=1+4+7, ch2=2+5) */ int channel_mixes = selected_channels / max; if (channel_mixes <= 0) /* ??? */ channel_mixes = 1; if (current < selected_channels % (channel_mixes * max)) /* may be simplified? */ channel_mixes += 1; volume = 1 / sqrt(channel_mixes); /* "power" add */ } //;VGM_LOG("MIX: layer ch=%i, cur=%i, v=%f\n", ch, current, volume); mixing_push_add(vgmstream, current, max + ch, volume); /* ch adjusted considering upmixed channels */ current++; if (current >= max) current = 0; } /* remove all mixed channels */ mixing_push_killmix(vgmstream, max); } void mixing_macro_crosstrack(VGMSTREAM* vgmstream, int max) { mixing_data *data = vgmstream->mixing_data; int current, ch, track, track_ch, track_num, output_channels; int32_t change_pos, change_next, change_time; if (!data) return; if (max <= 0 || data->output_channels <= max) return; if (!vgmstream->loop_flag) /* maybe force loop? */ return; /* this probably only makes sense for even channels so upmix before if needed) */ output_channels = data->output_channels; if (output_channels % 2) { mixing_push_upmix(vgmstream, output_channels); output_channels += 1; } /* set loops to hear all track changes */ track_num = output_channels / max; if (vgmstream->config.loop_count < track_num) vgmstream->config.loop_count = track_num; ch = 0; for (track = 0; track < track_num; track++) { double volume = 1.0; /* won't play at the same time, no volume change needed */ int loop_pre = vgmstream->loop_start_sample; int loop_samples = vgmstream->loop_end_sample - vgmstream->loop_start_sample; change_pos = loop_pre + loop_samples * track; change_next = loop_pre + loop_samples * (track + 1); change_time = 15.0 * vgmstream->sample_rate; /* in secs */ for (track_ch = 0; track_ch < max; track_ch++) { if (track > 0) { /* fade-in when prev track fades-out */ mixing_push_fade(vgmstream, ch + track_ch, 0.0, volume, '(', -1, change_pos, change_pos + change_time, -1); } if (track + 1 < track_num) { /* fade-out when next track fades-in */ mixing_push_fade(vgmstream, ch + track_ch, volume, 0.0, ')', -1, change_next, change_next + change_time, -1); } } ch += max; } /* mix all tracks into first */ current = 0; for (ch = max; ch < output_channels; ch++) { mixing_push_add(vgmstream, current, ch, 1.0); /* won't play at the same time, no volume change needed */ current++; if (current >= max) current = 0; } /* remove unneeded channels */ mixing_push_killmix(vgmstream, max); } void mixing_macro_crosslayer(VGMSTREAM* vgmstream, int max, char mode) { mixing_data *data = vgmstream->mixing_data; int current, ch, layer, layer_ch, layer_num, loop, output_channels; int32_t change_pos, change_time; if (!data) return; if (max <= 0 || data->output_channels <= max) return; if (!vgmstream->loop_flag) /* maybe force loop? */ return; /* this probably only makes sense for even channels so upmix before if needed) */ output_channels = data->output_channels; if (output_channels % 2) { mixing_push_upmix(vgmstream, output_channels); output_channels += 1; } /* set loops to hear all track changes */ layer_num = output_channels / max; if (vgmstream->config.loop_count < layer_num) vgmstream->config.loop_count = layer_num; /* mode 'v': constant volume * mode 'e': sets fades to successively lower/equalize volume per loop for each layer * (to keep final volume constant-ish), ex. 3 layers/loops, 2 max: * - layer0 (ch0+1): loop0 --[1.0]--, loop1 )=1.0..0.7, loop2 )=0.7..0.5, loop3 --[0.5/end]-- * - layer1 (ch2+3): loop0 --[0.0]--, loop1 (=0.0..0.7, loop2 )=0.7..0.5, loop3 --[0.5/end]-- * - layer2 (ch4+5): loop0 --[0.0]--, loop1 ---[0.0]--, loop2 (=0.0..0.5, loop3 --[0.5/end]-- * mode 'b': similar but 1st layer (main) has higher/delayed volume: * - layer0 (ch0+1): loop0 --[1.0]--, loop1 )=1.0..1.0, loop2 )=1.0..0.7, loop3 --[0.7/end]-- */ for (loop = 1; loop < layer_num; loop++) { double volume1 = 1.0; double volume2 = 1.0; int loop_pre = vgmstream->loop_start_sample; int loop_samples = vgmstream->loop_end_sample - vgmstream->loop_start_sample; change_pos = loop_pre + loop_samples * loop; change_time = 10.0 * vgmstream->sample_rate; /* in secs */ if (mode == 'e') { volume1 = 1 / sqrt(loop + 0); volume2 = 1 / sqrt(loop + 1); } ch = 0; for (layer = 0; layer < layer_num; layer++) { char type; if (mode == 'b') { if (layer == 0) { volume1 = 1 / sqrt(loop - 1 <= 0 ? 1 : loop - 1); volume2 = 1 / sqrt(loop + 0); } else { volume1 = 1 / sqrt(loop + 0); volume2 = 1 / sqrt(loop + 1); } } if (layer > loop) { /* not playing yet (volume is implicitly 0.0 from first fade in) */ continue; } else if (layer == loop) { /* fades in for the first time */ volume1 = 0.0; type = '('; } else { /* otherwise fades out to match other layers's volume */ type = ')'; } //;VGM_LOG("MIX: loop=%i, layer %i, vol1=%f, vol2=%f\n", loop, layer, volume1, volume2); for (layer_ch = 0; layer_ch < max; layer_ch++) { mixing_push_fade(vgmstream, ch + layer_ch, volume1, volume2, type, -1, change_pos, change_pos + change_time, -1); } ch += max; } } /* mix all tracks into first */ current = 0; for (ch = max; ch < output_channels; ch++) { mixing_push_add(vgmstream, current, ch, 1.0); current++; if (current >= max) current = 0; } /* remove unneeded channels */ mixing_push_killmix(vgmstream, max); } typedef enum { pos_FL = 0, pos_FR = 1, pos_FC = 2, pos_LFE = 3, pos_BL = 4, pos_BR = 5, pos_FLC = 6, pos_FRC = 7, pos_BC = 8, pos_SL = 9, pos_SR = 10, } mixing_position_t; void mixing_macro_downmix(VGMSTREAM* vgmstream, int max /*, mapping_t output_mapping*/) { mixing_data *data = vgmstream->mixing_data; int ch, output_channels, mp_in, mp_out, ch_in, ch_out; mapping_t input_mapping, output_mapping; const double vol_max = 1.0; const double vol_sqrt = 1 / sqrt(2); const double vol_half = 1 / 2; double matrix[16][16] = {{0}}; if (!data) return; if (max <= 1 || data->output_channels <= max || max >= 8) return; /* assume WAV defaults if not set */ input_mapping = vgmstream->channel_layout; if (input_mapping == 0) { switch(data->output_channels) { case 1: input_mapping = mapping_MONO; break; case 2: input_mapping = mapping_STEREO; break; case 3: input_mapping = mapping_2POINT1; break; case 4: input_mapping = mapping_QUAD; break; case 5: input_mapping = mapping_5POINT0; break; case 6: input_mapping = mapping_5POINT1; break; case 7: input_mapping = mapping_7POINT0; break; case 8: input_mapping = mapping_7POINT1; break; default: return; } } /* build mapping matrix[input channel][output channel] = volume, * using standard WAV/AC3 downmix formulas * - https://www.audiokinetic.com/library/edge/?source=Help&id=downmix_tables * - https://www.audiokinetic.com/library/edge/?source=Help&id=standard_configurations */ switch(max) { case 1: output_mapping = mapping_MONO; matrix[pos_FL][pos_FC] = vol_sqrt; matrix[pos_FR][pos_FC] = vol_sqrt; matrix[pos_FC][pos_FC] = vol_max; matrix[pos_SL][pos_FC] = vol_half; matrix[pos_SR][pos_FC] = vol_half; matrix[pos_BL][pos_FC] = vol_half; matrix[pos_BR][pos_FC] = vol_half; break; case 2: output_mapping = mapping_STEREO; matrix[pos_FL][pos_FL] = vol_max; matrix[pos_FR][pos_FR] = vol_max; matrix[pos_FC][pos_FL] = vol_sqrt; matrix[pos_FC][pos_FR] = vol_sqrt; matrix[pos_SL][pos_FL] = vol_sqrt; matrix[pos_SR][pos_FR] = vol_sqrt; matrix[pos_BL][pos_FL] = vol_sqrt; matrix[pos_BR][pos_FR] = vol_sqrt; break; default: /* not sure if +3ch would use FC/LFE, SL/BR and whatnot without passing extra config, so ignore for now */ return; } /* save and make N fake channels at the beginning for easier calcs */ output_channels = data->output_channels; for (ch = 0; ch < max; ch++) { mixing_push_upmix(vgmstream, 0); } /* downmix */ ch_in = 0; for (mp_in = 0; mp_in < 16; mp_in++) { /* read input mapping (ex. 5.1) and find channel */ if (!(input_mapping & (1< max) break; } ch_in++; if (ch_in >= output_channels) break; } /* remove unneeded channels */ mixing_push_killmix(vgmstream, max); } /* ******************************************************************* */ void mixing_setup(VGMSTREAM * vgmstream, int32_t max_sample_count) { mixing_data *data = vgmstream->mixing_data; float *mixbuf_re = NULL; if (!data) goto fail; /* a bit wonky but eh... */ if (vgmstream->channel_layout && vgmstream->channels != data->output_channels) { vgmstream->channel_layout = 0; ((VGMSTREAM*)vgmstream->start_vgmstream)->channel_layout = 0; } /* special value to not actually enable anything (used to query values) */ if (max_sample_count <= 0) goto fail; /* create or alter internal buffer */ mixbuf_re = realloc(data->mixbuf, max_sample_count*data->mixing_channels*sizeof(float)); if (!mixbuf_re) goto fail; data->mixbuf = mixbuf_re; data->mixing_on = 1; /* since data exists on its own memory and pointer is already set * there is no need to propagate to start_vgmstream */ /* segments/layers are independant from external buffers and may always mix */ return; fail: return; } void mixing_info(VGMSTREAM * vgmstream, int *out_input_channels, int *out_output_channels) { mixing_data *data = vgmstream->mixing_data; int input_channels, output_channels; if (!data) goto fail; output_channels = data->output_channels; if (data->output_channels > vgmstream->channels) input_channels = data->output_channels; else input_channels = vgmstream->channels; if (out_input_channels) *out_input_channels = input_channels; if (out_output_channels) *out_output_channels = output_channels; //;VGM_LOG("MIX: channels %i, in=%i, out=%i, mix=%i\n", vgmstream->channels, input_channels, output_channels, data->mixing_channels); return; fail: return; }