godot/scene/io/resource_format_wav.cpp

/*************************************************************************/
/*  resource_format_wav.cpp                                              */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
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/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "resource_format_wav.h"
#include "os/file_access.h"
#include "scene/resources/sample.h"

RES ResourceFormatLoaderWAV::load(const String &p_path, const String &p_original_path, Error *r_error) {
	if (r_error)
		*r_error = ERR_FILE_CANT_OPEN;

	Error err;
	FileAccess *file = FileAccess::open(p_path, FileAccess::READ, &err);

	ERR_FAIL_COND_V(err != OK, RES());

	if (r_error)
		*r_error = ERR_FILE_CORRUPT;

	/* CHECK RIFF */
	char riff[5];
	riff[4] = 0;
	file->get_buffer((uint8_t *)&riff, 4); //RIFF

	if (riff[0] != 'R' || riff[1] != 'I' || riff[2] != 'F' || riff[3] != 'F') {

		file->close();
		memdelete(file);
		ERR_FAIL_V(RES());
	}

	/* GET FILESIZE */
	uint32_t filesize = file->get_32();

	/* CHECK WAVE */

	char wave[4];

	file->get_buffer((uint8_t *)&wave, 4); //RIFF

	if (wave[0] != 'W' || wave[1] != 'A' || wave[2] != 'V' || wave[3] != 'E') {

		file->close();
		memdelete(file);
		ERR_EXPLAIN("Not a WAV file (no WAVE RIFF Header)")
		ERR_FAIL_V(RES());
	}

	bool format_found = false;
	bool data_found = false;
	int format_bits = 0;
	int format_channels = 0;
	int format_freq = 0;
	Sample::LoopFormat loop = Sample::LOOP_NONE;
	int loop_begin = 0;
	int loop_end = 0;

	Ref<Sample> sample(memnew(Sample));

	while (!file->eof_reached()) {

		/* chunk */
		char chunkID[4];
		file->get_buffer((uint8_t *)&chunkID, 4); //RIFF

		/* chunk size */
		uint32_t chunksize = file->get_32();
		uint32_t file_pos = file->get_pos(); //save file pos, so we can skip to next chunk safely

		if (file->eof_reached()) {

			//ERR_PRINT("EOF REACH");
			break;
		}

		if (chunkID[0] == 'f' && chunkID[1] == 'm' && chunkID[2] == 't' && chunkID[3] == ' ' && !format_found) {
			/* IS FORMAT CHUNK */

			uint16_t compression_code = file->get_16();

			if (compression_code != 1) {
				ERR_PRINT("Format not supported for WAVE file (not PCM). Save WAVE files as uncompressed PCM instead.");
				break;
			}

			format_channels = file->get_16();
			if (format_channels != 1 && format_channels != 2) {

				ERR_PRINT("Format not supported for WAVE file (not stereo or mono)");
				break;
			}

			format_freq = file->get_32(); //sampling rate

			file->get_32(); // average bits/second (unused)
			file->get_16(); // block align (unused)
			format_bits = file->get_16(); // bits per sample

			if (format_bits % 8) {

				ERR_PRINT("Strange number of bits in sample (not 8,16,24,32)");
				break;
			}

			/* Dont need anything else, continue */
			format_found = true;
		}

		if (chunkID[0] == 'd' && chunkID[1] == 'a' && chunkID[2] == 't' && chunkID[3] == 'a' && !data_found) {
			/* IS FORMAT CHUNK */
			data_found = true;

			if (!format_found) {
				ERR_PRINT("'data' chunk before 'format' chunk found.");
				break;
			}

			int frames = chunksize;

			frames /= format_channels;
			frames /= (format_bits >> 3);

			/*print_line("chunksize: "+itos(chunksize));
			print_line("channels: "+itos(format_channels));
			print_line("bits: "+itos(format_bits));
*/
			sample->create(
					(format_bits == 8) ? Sample::FORMAT_PCM8 : Sample::FORMAT_PCM16,
					(format_channels == 2) ? true : false,
					frames);
			sample->set_mix_rate(format_freq);

			int len = frames;
			if (format_channels == 2)
				len *= 2;
			if (format_bits > 8)
				len *= 2;

			DVector<uint8_t> data;
			data.resize(len);
			DVector<uint8_t>::Write dataw = data.write();
			void *data_ptr = dataw.ptr();

			for (int i = 0; i < frames; i++) {

				for (int c = 0; c < format_channels; c++) {

					if (format_bits == 8) {
						// 8 bit samples are UNSIGNED

						uint8_t s = file->get_8();
						s -= 128;
						int8_t *sp = (int8_t *)&s;

						int8_t *data_ptr8 = &((int8_t *)data_ptr)[i * format_channels + c];

						*data_ptr8 = *sp;

					} else {
						//16+ bits samples are SIGNED
						// if sample is > 16 bits, just read extra bytes

						uint32_t data = 0;
						for (int b = 0; b < (format_bits >> 3); b++) {

							data |= ((uint32_t)file->get_8()) << (b * 8);
						}
						data <<= (32 - format_bits);

						int32_t s = data;

						int16_t *data_ptr16 = &((int16_t *)data_ptr)[i * format_channels + c];

						*data_ptr16 = s >> 16;
					}
				}
			}

			dataw = DVector<uint8_t>::Write();

			sample->set_data(data);

			if (file->eof_reached()) {
				file->close();
				memdelete(file);
				ERR_EXPLAIN("Premature end of file.");
				ERR_FAIL_V(RES());
			}
		}

		if (chunkID[0] == 's' && chunkID[1] == 'm' && chunkID[2] == 'p' && chunkID[3] == 'l') {
			//loop point info!

			for (int i = 0; i < 10; i++)
				file->get_32(); // i wish to know why should i do this... no doc!

			loop = file->get_32() ? Sample::LOOP_PING_PONG : Sample::LOOP_FORWARD;
			loop_begin = file->get_32();
			loop_end = file->get_32();
		}
		file->seek(file_pos + chunksize);
	}

	sample->set_loop_format(loop);
	sample->set_loop_begin(loop_begin);
	sample->set_loop_end(loop_end);

	file->close();
	memdelete(file);

	if (r_error)
		*r_error = OK;

	return sample;
}
void ResourceFormatLoaderWAV::get_recognized_extensions(List<String> *p_extensions) const {

	p_extensions->push_back("wav");
}
bool ResourceFormatLoaderWAV::handles_type(const String &p_type) const {

	return (p_type == "Sample");
}

String ResourceFormatLoaderWAV::get_resource_type(const String &p_path) const {

	if (p_path.extension().to_lower() == "wav")
		return "Sample";
	return "";
}