ref: 2b5de0bafc1ebe347e08617de7595c1ea507c0b9
dir: /src/i_sdlsound.c/
// Emacs style mode select -*- C++ -*- //----------------------------------------------------------------------------- // // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 2005-8 Simon Howard // Copyright(C) 2008 David Flater // // This program is free software; you can redistribute it and/or // modify it under the terms of the GNU General Public License // as published by the Free Software Foundation; either version 2 // of the License, or (at your option) any later version. // // This program 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 General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA // 02111-1307, USA. // // DESCRIPTION: // System interface for sound. // //----------------------------------------------------------------------------- #include "config.h" #include <stdio.h> #include <stdlib.h> #include <assert.h> #include "SDL.h" #include "SDL_mixer.h" #ifdef HAVE_LIBSAMPLERATE #include <samplerate.h> #endif #include "deh_str.h" #include "i_sound.h" #include "i_system.h" #include "m_argv.h" #include "w_wad.h" #include "z_zone.h" #include "doomtype.h" #define LOW_PASS_FILTER #define NUM_CHANNELS 16 static boolean sound_initialised = false; static sfxinfo_t *channels_playing[NUM_CHANNELS]; static int mixer_freq; static Uint16 mixer_format; static int mixer_channels; static boolean use_sfx_prefix; static void (*ExpandSoundData)(sfxinfo_t *sfxinfo, byte *data, int samplerate, int length) = NULL; int use_libsamplerate = 0; // When a sound stops, check if it is still playing. If it is not, // we can mark the sound data as CACHE to be freed back for other // means. static void ReleaseSoundOnChannel(int channel) { int i; sfxinfo_t *sfxinfo = channels_playing[channel]; if (sfxinfo == NULL) { return; } channels_playing[channel] = NULL; for (i=0; i<NUM_CHANNELS; ++i) { // Playing on this channel? if so, don't release. if (channels_playing[i] == sfxinfo) return; } // Not used on any channel, and can be safely released Z_ChangeTag(sfxinfo->driver_data, PU_CACHE); } // Allocate a new Mix_Chunk along with its data, storing // the result in the variable pointed to by variable static Mix_Chunk *AllocateChunk(sfxinfo_t *sfxinfo, uint32_t len) { Mix_Chunk *chunk; // Allocate the chunk and the audio buffer together chunk = Z_Malloc(len + sizeof(Mix_Chunk), PU_STATIC, &sfxinfo->driver_data); sfxinfo->driver_data = chunk; // Skip past the chunk structure for the audio buffer chunk->abuf = (byte *) (chunk + 1); chunk->alen = len; chunk->allocated = 1; chunk->volume = MIX_MAX_VOLUME; return chunk; } #ifdef HAVE_LIBSAMPLERATE // Returns the conversion mode for libsamplerate to use. static int SRC_ConversionMode(void) { switch (use_libsamplerate) { // 0 = disabled default: case 0: return -1; // Ascending numbers give higher quality case 1: return SRC_LINEAR; case 2: return SRC_ZERO_ORDER_HOLD; case 3: return SRC_SINC_FASTEST; case 4: return SRC_SINC_MEDIUM_QUALITY; case 5: return SRC_SINC_BEST_QUALITY; } } // libsamplerate-based generic sound expansion function for any sample rate // unsigned 8 bits --> signed 16 bits // mono --> stereo // samplerate --> mixer_freq // Returns number of clipped samples. // DWF 2008-02-10 with cleanups by Simon Howard. static void ExpandSoundData_SRC(sfxinfo_t *sfxinfo, byte *data, int samplerate, int length) { SRC_DATA src_data; uint32_t i, abuf_index=0, clipped=0; uint32_t alen; int retn; int16_t *expanded; Mix_Chunk *chunk; src_data.input_frames = length; src_data.data_in = malloc(length * sizeof(float)); src_data.src_ratio = (double)mixer_freq / samplerate; // We include some extra space here in case of rounding-up. src_data.output_frames = src_data.src_ratio * length + (mixer_freq / 4); src_data.data_out = malloc(src_data.output_frames * sizeof(float)); assert(src_data.data_in != NULL && src_data.data_out != NULL); // Convert input data to floats for (i=0; i<length; ++i) { // Unclear whether 128 should be interpreted as "zero" or whether a // symmetrical range should be assumed. The following assumes a // symmetrical range. src_data.data_in[i] = data[i] / 127.5 - 1; } // Do the sound conversion retn = src_simple(&src_data, SRC_ConversionMode(), 1); assert(retn == 0); // Allocate the new chunk. alen = src_data.output_frames_gen * 4; chunk = AllocateChunk(sfxinfo, src_data.output_frames_gen * 4); expanded = (int16_t *) chunk->abuf; // Convert the result back into 16-bit integers. for (i=0; i<src_data.output_frames_gen; ++i) { // libsamplerate does not limit itself to the -1.0 .. 1.0 range on // output, so a multiplier less than INT16_MAX (32767) is required // to avoid overflows or clipping. However, the smaller the // multiplier, the quieter the sound effects get, and the more you // have to turn down the music to keep it in balance. // 22265 is the largest multiplier that can be used to resample all // of the Vanilla DOOM sound effects to 48 kHz without clipping // using SRC_SINC_BEST_QUALITY. It is close enough (only slightly // too conservative) for SRC_SINC_MEDIUM_QUALITY and // SRC_SINC_FASTEST. PWADs with interestingly different sound // effects or target rates other than 48 kHz might still result in // clipping--I don't know if there's a limit to it. // As the number of clipped samples increases, the signal is // gradually overtaken by noise, with the loudest parts going first. // However, a moderate amount of clipping is often tolerated in the // quest for the loudest possible sound overall. The results of // using INT16_MAX as the multiplier are not all that bad, but // artifacts are noticeable during the loudest parts. float cvtval_f = src_data.data_out[i] * 22265; int32_t cvtval_i = cvtval_f + (cvtval_f < 0 ? -0.5 : 0.5); // Asymmetrical sound worries me, so we won't use -32768. if (cvtval_i < -INT16_MAX) { cvtval_i = -INT16_MAX; ++clipped; } else if (cvtval_i > INT16_MAX) { cvtval_i = INT16_MAX; ++clipped; } // Left and right channels expanded[abuf_index++] = cvtval_i; expanded[abuf_index++] = cvtval_i; } free(src_data.data_in); free(src_data.data_out); if (clipped > 0) { fprintf(stderr, "Sound '%s': clipped %u samples (%0.2f %%)\n", sfxinfo->name, clipped, 400.0 * clipped / chunk->alen); } } #endif static boolean ConvertibleRatio(int freq1, int freq2) { int ratio; if (freq1 > freq2) { return ConvertibleRatio(freq2, freq1); } else if ((freq2 % freq1) != 0) { // Not in a direct ratio return false; } else { // Check the ratio is a power of 2 ratio = freq2 / freq1; while ((ratio & 1) == 0) { ratio = ratio >> 1; } return ratio == 1; } } // Generic sound expansion function for any sample rate. // Returns number of clipped samples (always 0). static void ExpandSoundData_SDL(sfxinfo_t *sfxinfo, byte *data, int samplerate, int length) { SDL_AudioCVT convertor; Mix_Chunk *chunk; uint32_t expanded_length; // Calculate the length of the expanded version of the sample. expanded_length = (uint32_t) ((((uint64_t) length) * mixer_freq) / samplerate); // Double up twice: 8 -> 16 bit and mono -> stereo expanded_length *= 4; // Allocate a chunk in which to expand the sound chunk = AllocateChunk(sfxinfo, expanded_length); // If we can, use the standard / optimised SDL conversion routines. if (samplerate <= mixer_freq && ConvertibleRatio(samplerate, mixer_freq) && SDL_BuildAudioCVT(&convertor, AUDIO_U8, 1, samplerate, mixer_format, mixer_channels, mixer_freq)) { convertor.buf = chunk->abuf; convertor.len = length; memcpy(convertor.buf, data, length); SDL_ConvertAudio(&convertor); } else { Sint16 *expanded = (Sint16 *) chunk->abuf; int expanded_length; int expand_ratio; int i; // Generic expansion if conversion does not work: // // SDL's audio conversion only works for rate conversions that are // powers of 2; if the two formats are not in a direct power of 2 // ratio, do this naive conversion instead. // number of samples in the converted sound expanded_length = ((uint64_t) length * mixer_freq) / samplerate; expand_ratio = (length << 8) / expanded_length; for (i=0; i<expanded_length; ++i) { Sint16 sample; int src; src = (i * expand_ratio) >> 8; sample = data[src] | (data[src] << 8); sample -= 32768; // expand 8->16 bits, mono->stereo expanded[i * 2] = expanded[i * 2 + 1] = sample; } #ifdef LOW_PASS_FILTER // Perform a low-pass filter on the upscaled sound to filter // out high-frequency noise from the conversion process. { float rc, dt, alpha; // Low-pass filter for cutoff frequency f: // // For sampling rate r, dt = 1 / r // rc = 1 / 2*pi*f // alpha = dt / (rc + dt) // Filter to the half sample rate of the original sound effect // (maximum frequency, by nyquist) dt = 1.0f / mixer_freq; rc = 1.0f / (3.14f * samplerate); alpha = dt / (rc + dt); for (i=1; i<expanded_length; ++i) { expanded[i] = (Sint16) (alpha * expanded[i] + (1 - alpha) * expanded[i-1]); } } #endif /* #ifdef LOW_PASS_FILTER */ } } // Load and convert a sound effect // Returns true if successful static boolean CacheSFX(sfxinfo_t *sfxinfo) { int lumpnum; unsigned int lumplen; int samplerate; unsigned int length; byte *data; // need to load the sound lumpnum = sfxinfo->lumpnum; data = W_CacheLumpNum(lumpnum, PU_STATIC); lumplen = W_LumpLength(lumpnum); // Check the header, and ensure this is a valid sound if (lumplen < 8 || data[0] != 0x03 || data[1] != 0x00) { // Invalid sound return false; } // 16 bit sample rate field, 32 bit length field samplerate = (data[3] << 8) | data[2]; length = (data[7] << 24) | (data[6] << 16) | (data[5] << 8) | data[4]; // If the header specifies that the length of the sound is greater than // the length of the lump itself, this is an invalid sound lump if (length > lumplen - 8) { return false; } // Sample rate conversion ExpandSoundData(sfxinfo, data + 8, samplerate, length); // don't need the original lump any more W_ReleaseLumpNum(lumpnum); return true; } static void GetSfxLumpName(sfxinfo_t *sfx, char *buf) { // Linked sfx lumps? Get the lump number for the sound linked to. if (sfx->link != NULL) { sfx = sfx->link; } // Doom adds a DS* prefix to sound lumps; Heretic and Hexen don't // do this. if (use_sfx_prefix) { sprintf(buf, "ds%s", DEH_String(sfx->name)); } else { strcpy(buf, DEH_String(sfx->name)); } } #ifdef HAVE_LIBSAMPLERATE // Preload all the sound effects - stops nasty ingame freezes static void I_SDL_PrecacheSounds(sfxinfo_t *sounds, int num_sounds) { char namebuf[9]; int i; // Don't need to precache the sounds unless we are using libsamplerate. if (use_libsamplerate == 0) { return; } printf("I_SDL_PrecacheSounds: Precaching all sound effects.."); for (i=0; i<num_sounds; ++i) { if ((i % 6) == 0) { printf("."); fflush(stdout); } GetSfxLumpName(&sounds[i], namebuf); sounds[i].lumpnum = W_CheckNumForName(namebuf); if (sounds[i].lumpnum != -1) { // Try to cache the sound and then release it as cache if (CacheSFX(&sounds[i])) { Z_ChangeTag(sounds[i].driver_data, PU_CACHE); } } } printf("\n"); } #else static void I_SDL_PrecacheSounds(sfxinfo_t *sounds, int num_sounds) { // no-op } #endif // Load a SFX chunk into memory and ensure that it is locked. static boolean LockSound(sfxinfo_t *sfxinfo) { // If the sound isn't loaded, load it now if (sfxinfo->driver_data == NULL) { if (!CacheSFX(sfxinfo)) { return false; } } else { // Lock the sound effect into memory Z_ChangeTag(sfxinfo->driver_data, PU_STATIC); } return true; } // // Retrieve the raw data lump index // for a given SFX name. // static int I_SDL_GetSfxLumpNum(sfxinfo_t *sfx) { char namebuf[9]; GetSfxLumpName(sfx, namebuf); return W_GetNumForName(namebuf); } static void I_SDL_UpdateSoundParams(int handle, int vol, int sep) { int left, right; if (!sound_initialised) { return; } left = ((254 - sep) * vol) / 127; right = ((sep) * vol) / 127; if (left < 0) left = 0; else if ( left > 255) left = 255; if (right < 0) right = 0; else if (right > 255) right = 255; Mix_SetPanning(handle, left, right); } // // Starting a sound means adding it // to the current list of active sounds // in the internal channels. // As the SFX info struct contains // e.g. a pointer to the raw data, // it is ignored. // As our sound handling does not handle // priority, it is ignored. // Pitching (that is, increased speed of playback) // is set, but currently not used by mixing. // static int I_SDL_StartSound(sfxinfo_t *sfxinfo, int channel, int vol, int sep) { Mix_Chunk *chunk; if (!sound_initialised) { return -1; } // Release a sound effect if there is already one playing // on this channel ReleaseSoundOnChannel(channel); // Get the sound data if (!LockSound(sfxinfo)) { return -1; } chunk = (Mix_Chunk *) sfxinfo->driver_data; // play sound Mix_PlayChannelTimed(channel, chunk, 0, -1); channels_playing[channel] = sfxinfo; // set separation, etc. I_SDL_UpdateSoundParams(channel, vol, sep); return channel; } static void I_SDL_StopSound (int handle) { if (!sound_initialised) { return; } Mix_HaltChannel(handle); // Sound data is no longer needed; release the // sound data being used for this channel ReleaseSoundOnChannel(handle); } static boolean I_SDL_SoundIsPlaying(int handle) { if (handle < 0) { return false; } return Mix_Playing(handle); } // // Periodically called to update the sound system // static void I_SDL_UpdateSound(void) { int i; // Check all channels to see if a sound has finished for (i=0; i<NUM_CHANNELS; ++i) { if (channels_playing[i] && !I_SDL_SoundIsPlaying(i)) { // Sound has finished playing on this channel, // but sound data has not been released to cache ReleaseSoundOnChannel(i); } } } static void I_SDL_ShutdownSound(void) { if (!sound_initialised) { return; } Mix_CloseAudio(); SDL_QuitSubSystem(SDL_INIT_AUDIO); sound_initialised = false; } static boolean I_SDL_InitSound(boolean _use_sfx_prefix) { int i; use_sfx_prefix = _use_sfx_prefix; // No sounds yet for (i=0; i<NUM_CHANNELS; ++i) { channels_playing[i] = NULL; } if (SDL_Init(SDL_INIT_AUDIO) < 0) { fprintf(stderr, "Unable to set up sound.\n"); return false; } if (Mix_OpenAudio(snd_samplerate, AUDIO_S16SYS, 2, 1024) < 0) { fprintf(stderr, "Error initialising SDL_mixer: %s\n", Mix_GetError()); return false; } ExpandSoundData = ExpandSoundData_SDL; Mix_QuerySpec(&mixer_freq, &mixer_format, &mixer_channels); #ifdef HAVE_LIBSAMPLERATE if (use_libsamplerate != 0) { if (SRC_ConversionMode() < 0) { I_Error("I_SDL_InitSound: Invalid value for use_libsamplerate: %i", use_libsamplerate); } ExpandSoundData = ExpandSoundData_SRC; } #else if (use_libsamplerate != 0) { fprintf(stderr, "I_SDL_InitSound: use_libsamplerate=%i, but " "libsamplerate support not compiled in.\n", use_libsamplerate); } #endif Mix_AllocateChannels(NUM_CHANNELS); SDL_PauseAudio(0); sound_initialised = true; return true; } static snddevice_t sound_sdl_devices[] = { SNDDEVICE_SB, SNDDEVICE_PAS, SNDDEVICE_GUS, SNDDEVICE_WAVEBLASTER, SNDDEVICE_SOUNDCANVAS, SNDDEVICE_AWE32, }; sound_module_t sound_sdl_module = { sound_sdl_devices, arrlen(sound_sdl_devices), I_SDL_InitSound, I_SDL_ShutdownSound, I_SDL_GetSfxLumpNum, I_SDL_UpdateSound, I_SDL_UpdateSoundParams, I_SDL_StartSound, I_SDL_StopSound, I_SDL_SoundIsPlaying, I_SDL_PrecacheSounds, };