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Diffstat (limited to 'trunk/src/lib/formats/lviv_lvt.c')
-rw-r--r--trunk/src/lib/formats/lviv_lvt.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/trunk/src/lib/formats/lviv_lvt.c b/trunk/src/lib/formats/lviv_lvt.c
new file mode 100644
index 00000000000..3f2ccce936b
--- /dev/null
+++ b/trunk/src/lib/formats/lviv_lvt.c
@@ -0,0 +1,149 @@
+/* .LVT tape images */
+#include "lviv_lvt.h"
+
+#define WAVEENTRY_LOW -32768
+#define WAVEENTRY_HIGH 32767
+
+#define LVIV_LVT_BIT_SAMPLES 60
+#define LVIV_LVT_HEADER_PILOT_SAMPLES 5190*60
+#define LVIV_LVT_HEADER_DATA_SAMPLES 16*11*60
+#define LVIV_LVT_PAUSE_SAMPLES 69370
+#define LVIV_LVT_BLOCK_PILOT_SAMPLES 1298*60
+
+#define LVIV_LVT_HEADER_PILOT_LENGTH 5190
+#define LVIV_LVT_BLOCK_PILOT_LENGTH 1298
+
+static INT16 *lviv_emit_level(INT16 *p, int count, int level)
+{
+ int i;
+
+ for (i=0; i<count; i++)
+ {
+ *(p++) = level;
+ }
+ return p;
+}
+
+static INT16* lviv_output_bit(INT16 *p, UINT8 b)
+{
+ if (b)
+ {
+ p = lviv_emit_level (p, 15, WAVEENTRY_HIGH);
+ p = lviv_emit_level (p, 15, WAVEENTRY_LOW);
+ p = lviv_emit_level (p, 15, WAVEENTRY_HIGH);
+ p = lviv_emit_level (p, 15, WAVEENTRY_LOW);
+ }
+ else
+ {
+ p = lviv_emit_level (p, 30, WAVEENTRY_HIGH);
+ p = lviv_emit_level (p, 30, WAVEENTRY_LOW);
+ }
+ return p;
+}
+
+static INT16* lviv_output_byte(INT16 *p, UINT8 byte)
+{
+ int i;
+
+ p = lviv_output_bit (p, 0);
+
+ for (i=0; i<8; i++)
+ p = lviv_output_bit(p,(byte>>i) & 0x01);
+
+ p = lviv_output_bit (p, 1);
+ p = lviv_output_bit (p, 1);
+ return p;
+}
+
+/*************************************************************************************/
+
+static int lviv_cassette_calculate_size_in_samples(const UINT8 *bytes, int length)
+{
+ int size;
+
+ size = LVIV_LVT_HEADER_PILOT_SAMPLES +
+ LVIV_LVT_HEADER_DATA_SAMPLES +
+ LVIV_LVT_PAUSE_SAMPLES +
+ LVIV_LVT_BLOCK_PILOT_SAMPLES +
+ (length-0x10)*11*LVIV_LVT_BIT_SAMPLES;
+
+ return size;
+}
+
+/*************************************************************************************/
+
+static int lviv_cassette_fill_wave(INT16 *buffer, int length, UINT8 *bytes)
+{
+ int i;
+ INT16 * p = buffer;
+
+ int data_size;
+
+ for (i=0; i<LVIV_LVT_HEADER_PILOT_LENGTH; i++)
+ p = lviv_output_bit (p, 1);
+
+ for (i=0; i<10; i++)
+ p = lviv_output_byte (p, bytes[0x09]);
+
+ for (i=0; i<6; i++)
+ p = lviv_output_byte (p, bytes[0x0a+i]);
+
+ p = lviv_emit_level (p, LVIV_LVT_PAUSE_SAMPLES, WAVEENTRY_HIGH);
+
+ for (i=0; i<LVIV_LVT_BLOCK_PILOT_LENGTH; i++)
+ p = lviv_output_bit (p, 1);
+
+ data_size = length - ( LVIV_LVT_HEADER_PILOT_SAMPLES +
+ LVIV_LVT_HEADER_DATA_SAMPLES +
+ LVIV_LVT_PAUSE_SAMPLES +
+ LVIV_LVT_BLOCK_PILOT_SAMPLES );
+ data_size/=660;
+
+ for (i=0; i<data_size; i++)
+ p = lviv_output_byte (p, bytes[0x10+i]);
+
+ return p - buffer;
+}
+
+
+
+static const struct CassetteLegacyWaveFiller lviv_legacy_fill_wave =
+{
+ lviv_cassette_fill_wave, /* fill_wave */
+ -1, /* chunk_size */
+ 0, /* chunk_samples */
+ lviv_cassette_calculate_size_in_samples, /* chunk_sample_calc */
+ 44100, /* sample_frequency */
+ 0, /* header_samples */
+ 0 /* trailer_samples */
+};
+
+
+
+static casserr_t lviv_lvt_identify(cassette_image *cassette, struct CassetteOptions *opts)
+{
+ return cassette_legacy_identify(cassette, opts, &lviv_legacy_fill_wave);
+}
+
+
+
+static casserr_t lviv_lvt_load(cassette_image *cassette)
+{
+ return cassette_legacy_construct(cassette, &lviv_legacy_fill_wave);
+}
+
+
+
+static const struct CassetteFormat lviv_lvt_image_format =
+{
+ "lvt",
+ lviv_lvt_identify,
+ lviv_lvt_load,
+ NULL
+};
+
+
+
+CASSETTE_FORMATLIST_START(lviv_lvt_format)
+ CASSETTE_FORMAT(lviv_lvt_image_format)
+CASSETTE_FORMATLIST_END