diff options
Diffstat (limited to 'src/combined/nsf_decoder.c')
-rw-r--r-- | src/combined/nsf_decoder.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/src/combined/nsf_decoder.c b/src/combined/nsf_decoder.c new file mode 100644 index 000000000..4ae920dfd --- /dev/null +++ b/src/combined/nsf_decoder.c @@ -0,0 +1,247 @@ +/* + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA + * + * NSF Audio "Decoder" using the Nosefart NSF engine by Matt Conte + * http://www.baisoku.org/ + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> +#include <unistd.h> + +#include <xine/xine_internal.h> +#include <xine/audio_out.h> +#include <xine/buffer.h> +#include <xine/xineutils.h> +#include "bswap.h" + +/* Nosefart includes */ +#include "types.h" +#include "nsf.h" + +#include "nsf_combined.h" + +typedef struct { + audio_decoder_class_t decoder_class; +} nsf_class_t; + +typedef struct nsf_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 */ + + int nsf_size; + unsigned char *nsf_file; + int nsf_index; + int song_number; + + /* nsf-specific variables */ + int64_t last_pts; + unsigned int iteration; + + nsf_t *nsf; +} nsf_decoder_t; + +/************************************************************************** + * xine audio plugin functions + *************************************************************************/ + +static void nsf_decode_data (audio_decoder_t *this_gen, buf_element_t *buf) { + + nsf_decoder_t *this = (nsf_decoder_t *) this_gen; + audio_buffer_t *audio_buffer; + + 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]; + + /* take this opportunity to initialize stream/meta information */ + _x_meta_info_set_utf8(this->stream, XINE_META_INFO_AUDIOCODEC, + "NES Music (Nosefart)"); + + this->song_number = buf->content[4]; + /* allocate a buffer for the file */ + this->nsf_size = _X_BE_32(&buf->content[0]); + this->nsf_file = calloc(1, this->nsf_size); + this->nsf_index = 0; + + /* peform any other required initialization */ + this->last_pts = -1; + this->iteration = 0; + + return; + } + + /* accumulate chunks from the NSF file until whole file is received */ + if (this->nsf_index < this->nsf_size) { + xine_fast_memcpy(&this->nsf_file[this->nsf_index], buf->content, + buf->size); + this->nsf_index += buf->size; + + if (this->nsf_index == this->nsf_size) { + /* file has been received, proceed to initialize engine */ + nsf_init(); + this->nsf = nsf_load(NULL, this->nsf_file, this->nsf_size); + if (!this->nsf) { + xprintf (this->stream->xine, XINE_VERBOSITY_DEBUG, "nsf: could not initialize NSF\n"); + /* make the decoder return on every subsequent buffer */ + this->nsf_index = 0; + return; + } + this->nsf->current_song = this->song_number; + nsf_playtrack(this->nsf, this->nsf->current_song, this->sample_rate, + this->bits_per_sample, this->channels); + } + 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, + this->bits_per_sample, + this->sample_rate, + _x_ao_channels2mode(this->channels)); + } + + /* if the audio still isn't open, do not go any further with the decode */ + if (!this->output_open) + return; + + /* check if a song change was requested */ + if (buf->decoder_info[1]) { + this->nsf->current_song = buf->decoder_info[1]; + nsf_playtrack(this->nsf, this->nsf->current_song, this->sample_rate, + this->bits_per_sample, this->channels); + } + + /* time to decode a frame */ + if (this->last_pts != -1) { + + /* process a frame */ + nsf_frame(this->nsf); + + /* get an audio buffer */ + audio_buffer = this->stream->audio_out->get_buffer (this->stream->audio_out); + if (audio_buffer->mem_size == 0) { + xprintf (this->stream->xine, XINE_VERBOSITY_DEBUG, "nsf: Help! Allocated audio buffer with nothing in it!\n"); + return; + } + + apu_process(audio_buffer->mem, this->sample_rate / this->nsf->playback_rate); + audio_buffer->vpts = buf->pts; + audio_buffer->num_frames = this->sample_rate / this->nsf->playback_rate; + this->stream->audio_out->put_buffer (this->stream->audio_out, audio_buffer, this->stream); + } + this->last_pts = buf->pts; +} + +/* This function resets the state of the audio decoder. This usually + * entails resetting the data accumulation buffer. */ +static void nsf_reset (audio_decoder_t *this_gen) { + + nsf_decoder_t *this = (nsf_decoder_t *) this_gen; + + this->last_pts = -1; +} + +/* This function resets the last pts value of the audio decoder. */ +static void nsf_discontinuity (audio_decoder_t *this_gen) { + + nsf_decoder_t *this = (nsf_decoder_t *) this_gen; + + this->last_pts = -1; +} + +/* This function closes the audio output and frees the private audio decoder + * structure. */ +static void nsf_dispose (audio_decoder_t *this_gen) { + + nsf_decoder_t *this = (nsf_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 */ + nsf_free(&this->nsf); + free(this->nsf_file); + 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) { + + nsf_decoder_t *this ; + + this = (nsf_decoder_t *) calloc(1, sizeof(nsf_decoder_t)); + + /* connect the member functions */ + this->audio_decoder.decode_data = nsf_decode_data; + this->audio_decoder.reset = nsf_reset; + this->audio_decoder.discontinuity = nsf_discontinuity; + this->audio_decoder.dispose = nsf_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; + + /* return the newly-initialized audio decoder */ + return &this->audio_decoder; +} + +/* This function allocates a private audio decoder class and initializes + * the class's member functions. */ +void *decoder_nsf_init_plugin (xine_t *xine, void *data) { + + nsf_class_t *this ; + + this = (nsf_class_t *) calloc(1, sizeof(nsf_class_t)); + + this->decoder_class.open_plugin = open_plugin; + this->decoder_class.identifier = "NSF"; + this->decoder_class.description = N_("NES Music audio decoder plugin"); + this->decoder_class.dispose = default_audio_decoder_class_dispose; + + return this; +} |