/* 2004.02.01 first released source code for IOMP */ /* * Copyright (C) 2000-2001 the xine project * * This file is part of xine, a free video player. * * xine 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. * * xine 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 * * Interplay DPCM Audio Decoder by Mike Melanson (melanson@pcisys.net) * For more information regarding the Interplay MVE file format, visit: * http://www.pcisys.net/~melanson/codecs/ * * $Id: interplayaudio.c,v 1.2 2003/11/25 04:26:03 georgedon Exp $ */ #include #include #include #include #include #include "xine_internal.h" #include "audio_out.h" #include "buffer.h" #include "xineutils.h" #include "bswap.h" #define AUDIOBUFSIZE 128*1024 typedef struct { audio_decoder_class_t decoder_class; } interplay_class_t; typedef struct interplay_decoder_s { audio_decoder_t audio_decoder; xine_stream_t *stream; int sample_rate; /* audio sample rate */ int bits_per_sample; /* bits/sample, usually 8 or 16 */ int channels; /* 1 or 2, usually */ int output_open; /* flag to indicate audio is ready */ unsigned char *buf; /* data accumulation buffer */ int bufsize; /* maximum size of buf */ int size; /* size of accumulated data in buf */ int last_left_delta; int last_right_delta; } interplay_decoder_t; /************************************************************************** * Interplay DPCM specific decode functions *************************************************************************/ int interplay_delta_table[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 47, 51, 56, 61, 66, 72, 79, 86, 94, 102, 112, 122, 133, 145, 158, 173, 189, 206, 225, 245, 267, 292, 318, 348, 379, 414, 452, 493, 538, 587, 640, 699, 763, 832, 908, 991, 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993, 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008, 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059, 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206, 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589, -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1, 1, 1, 5481, 10503, 15105, 19322, 23186, 26728, 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298, -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597, -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772, -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373, -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180, -1081, -991, -908, -832, -763, -699, -640, -587, -538, -493, -452, -414, -379, -348, -318, -292, -267, -245, -225, -206, -189, -173, -158, -145, -133, -122, -112, -102, -94, -86, -79, -72, -66, -61, -56, -51, -47, -43, -42, -41, -40, -39, -38, -37, -36, -35, -34, -33, -32, -31, -30, -29, -28, -27, -26, -25, -24, -23, -22, -21, -20, -19, -18, -17, -16, -15, -14, -13, -12, -11, -10, -9, -8, -7, -6, -5, -4, -3, -2, -1 }; /************************************************************************** * xine audio plugin functions *************************************************************************/ /* clamp a number within a signed 16-bit range */ #define CLAMP_S16(x) if (x < -32768) x = -32768; \ else if (x > 32767) x = 32767; static void interplay_decode_data (audio_decoder_t *this_gen, buf_element_t *buf) { interplay_decoder_t *this = (interplay_decoder_t *) this_gen; audio_buffer_t *audio_buffer; int i; int samples_to_send; int delta[2]; int stream_ptr = 0; int sequence_number; int channel_number = 0; if (buf->decoder_flags & BUF_FLAG_HEADER) { /* When the engine sends a BUF_FLAG_HEADER flag, it is time to initialize * the decoder. The buffer element type has 4 decoder_info fields, * 0..3. Field 1 is the sample rate. Field 2 is the bits/sample. Field * 3 is the number of channels. */ this->sample_rate = buf->decoder_info[1]; this->bits_per_sample = buf->decoder_info[2]; this->channels = buf->decoder_info[3]; /* initialize the data accumulation buffer */ this->buf = xine_xmalloc(AUDIOBUFSIZE); this->bufsize = AUDIOBUFSIZE; this->size = 0; /* take this opportunity to initialize stream/meta information */ this->stream->meta_info[XINE_META_INFO_AUDIOCODEC] = strdup("Interplay MVE DPCM"); return; } /* if the audio output is not open yet, open the audio output */ if (!this->output_open) { this->output_open = this->stream->audio_out->open( this->stream->audio_out, this->stream, 16, this->sample_rate, (this->channels == 2) ? AO_CAP_MODE_STEREO : AO_CAP_MODE_MONO); } /* if the audio still isn't open, do not go any further with the decode */ if (!this->output_open) return; /* accumulate the data passed through the buffer element type; increase * the accumulator buffer size as necessary */ if( this->size + buf->size > this->bufsize ) { this->bufsize = this->size + 2 * buf->size; printf("interplayaudio: increasing source buffer to %d to avoid overflow.\n", this->bufsize); this->buf = realloc( this->buf, this->bufsize ); } xine_fast_memcpy (&this->buf[this->size], buf->content, buf->size); this->size += buf->size; /* When a buffer element type has the BUF_FLAG_FRAME_END flag set, it is * time to decode the data in the buffer. */ if (buf->decoder_flags & BUF_FLAG_FRAME_END) { /* if this is the first frame, fetch the first deltas from the stream */ sequence_number = LE_16(&this->buf[stream_ptr]); stream_ptr += 6; /* skip over the stream mask and stream length */ if (sequence_number == 1) { delta[0] = LE_16(&this->buf[stream_ptr]); stream_ptr += 2; if (this->channels == 2) { delta[1] = LE_16(&this->buf[stream_ptr]); stream_ptr += 2; } } else { delta[0] = this->last_left_delta; if (this->channels == 2) delta[1] = this->last_right_delta; } /* iterate through each 8-bit delta in the input buffer */ while (stream_ptr < this->size) { audio_buffer = this->stream->audio_out->get_buffer (this->stream->audio_out); if (audio_buffer->mem_size == 0) { printf ("interplayaudio: Help! Allocated audio buffer with nothing in it!\n"); return; } /* this->size and stream_ptr are sample counts, mem_size is a byte count */ if ((this->size - stream_ptr) > (audio_buffer->mem_size / 2)) samples_to_send = audio_buffer->mem_size / 2; else samples_to_send = this->size - stream_ptr; /* fill up this buffer */ for (i = 0; i < samples_to_send; i++) { delta[channel_number] += interplay_delta_table[this->buf[stream_ptr++]]; CLAMP_S16(delta[channel_number]); audio_buffer->mem[i] = delta[channel_number]; /* toggle channel */ channel_number ^= this->channels - 1; } audio_buffer->num_frames = samples_to_send / this->channels; audio_buffer->vpts = buf->pts; buf->pts = 0; /* only first buffer gets the real pts */ this->stream->audio_out->put_buffer (this->stream->audio_out, audio_buffer, this->stream); } /* stash away the deltas for the next block */ this->last_left_delta = delta[0]; this->last_right_delta = delta[1]; /* reset data accumulation buffer */ this->size = 0; } } /* This function resets the state of the audio decoder. This usually * entails resetting the data accumulation buffer. */ static void interplay_reset (audio_decoder_t *this_gen) { interplay_decoder_t *this = (interplay_decoder_t *) this_gen; this->size = 0; } /* This function resets the last pts value of the audio decoder. */ static void interplay_discontinuity (audio_decoder_t *this_gen) { } /* This function closes the audio output and frees the private audio decoder * structure. */ static void interplay_dispose (audio_decoder_t *this_gen) { interplay_decoder_t *this = (interplay_decoder_t *) this_gen; /* close the audio output */ if (this->output_open) this->stream->audio_out->close (this->stream->audio_out, this->stream); this->output_open = 0; /* free anything that was allocated during operation */ free(this->buf); free(this); } /* This function allocates, initializes, and returns a private audio * decoder structure. */ static audio_decoder_t *open_plugin (audio_decoder_class_t *class_gen, xine_stream_t *stream) { interplay_decoder_t *this ; this = (interplay_decoder_t *) malloc (sizeof (interplay_decoder_t)); /* connect the member functions */ this->audio_decoder.decode_data = interplay_decode_data; this->audio_decoder.reset = interplay_reset; this->audio_decoder.discontinuity = interplay_discontinuity; this->audio_decoder.dispose = interplay_dispose; /* connect the stream */ this->stream = stream; /* audio output is not open at the start */ this->output_open = 0; /* initialize the basic audio parameters */ this->channels = 0; this->sample_rate = 0; this->bits_per_sample = 0; /* initialize the data accumulation buffer */ this->buf = NULL; this->bufsize = 0; this->size = 0; /* return the newly-initialized audio decoder */ return &this->audio_decoder; } /* This function returns a brief string that describes (usually with the * decoder's most basic name) the audio decoder plugin. */ static char *get_identifier (audio_decoder_class_t *this) { return "Interplay DPCM Audio"; } /* This function returns a slightly longer string describing the audio * decoder plugin. */ static char *get_description (audio_decoder_class_t *this) { return "Interplay DPCM audio decoder plugin"; } /* This function frees the audio decoder class and any other memory that was * allocated. */ static void dispose_class (audio_decoder_class_t *this_gen) { interplay_class_t *this = (interplay_class_t *)this_gen; free (this); } /* This function allocates a private audio decoder class and initializes * the class's member functions. */ static void *init_plugin (xine_t *xine, void *data) { interplay_class_t *this ; this = (interplay_class_t *) malloc (sizeof (interplay_class_t)); this->decoder_class.open_plugin = open_plugin; this->decoder_class.get_identifier = get_identifier; this->decoder_class.get_description = get_description; this->decoder_class.dispose = dispose_class; return this; } /* This is a list of all of the internal xine audio buffer types that * this decoder is able to handle. Check src/xine-engine/buffer.h for a * list of valid buffer types (and add a new one if the one you need does * not exist). Terminate the list with a 0. */ static uint32_t audio_types[] = { BUF_AUDIO_INTERPLAY, 0 }; /* This data structure combines the list of supported xine buffer types and * the priority that the plugin should be given with respect to other * plugins that handle the same buffer type. A plugin with priority (n+1) * will be used instead of a plugin with priority (n). */ static decoder_info_t dec_info_audio = { audio_types, /* supported types */ 5 /* priority */ }; /* The plugin catalog entry. This is the only information that this plugin * will export to the public. */ plugin_info_t xine_plugin_info[] = { /* { type, API version, "name", version, special_info, init_function }, */ { PLUGIN_AUDIO_DECODER, 13, "interplayaudio", XINE_VERSION_CODE, &dec_info_audio, &init_plugin }, { PLUGIN_NONE, 0, "", 0, NULL, NULL } };