+++ /dev/null
-#include "funcprotos.h"
-#include "ima4.h"
-#include "quicktime.h"
-
-typedef struct
-{
-/* During decoding the work_buffer contains the most recently read chunk. */
-/* During encoding the work_buffer contains interlaced overflow samples */
-/* from the last chunk written. */
- int16_t *work_buffer;
- unsigned char *read_buffer; /* Temporary buffer for drive reads. */
-
-/* Starting information for all channels during encoding. */
- int *last_samples, *last_indexes;
- long chunk; /* Number of chunk in work buffer */
- int buffer_channel; /* Channel of work buffer */
-
-/* Number of samples in largest chunk read. */
-/* Number of samples plus overflow in largest chunk write, interlaced. */
- long work_size;
- long work_overflow; /* Number of overflow samples from the last chunk written. */
- long read_size; /* Size of read buffer. */
-} quicktime_ima4_codec_t;
-
-static int ima4_step[89] =
-{
- 7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
- 19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
- 50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
- 130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
- 337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
- 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
- 2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
- 5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
- 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
-};
-
-static int ima4_index[16] =
-{
- -1, -1, -1, -1, 2, 4, 6, 8,
- -1, -1, -1, -1, 2, 4, 6, 8
-};
-
-/* Known by divine revelation */
-
-#define BLOCK_SIZE 0x22
-#define SAMPLES_PER_BLOCK 0x40
-
-/* ================================== private for ima4 */
-
-
-void ima4_decode_sample(int *predictor, int *nibble, int *index, int *step)
-{
- int difference, sign;
-
-/* Get new index value */
- *index += ima4_index[*nibble];
-
- if(*index < 0) *index = 0;
- else
- if(*index > 88) *index = 88;
-
-/* Get sign and magnitude from *nibble */
- sign = *nibble & 8;
- *nibble = *nibble & 7;
-
-/* Get difference */
- difference = *step >> 3;
- if(*nibble & 4) difference += *step;
- if(*nibble & 2) difference += *step >> 1;
- if(*nibble & 1) difference += *step >> 2;
-
-/* Predict value */
- if(sign)
- *predictor -= difference;
- else
- *predictor += difference;
-
- if(*predictor > 32767) *predictor = 32767;
- else
- if(*predictor < -32768) *predictor = -32768;
-
-/* Update the step value */
- *step = ima4_step[*index];
-}
-
-void ima4_decode_block(quicktime_audio_map_t *atrack, int16_t *output, unsigned char *input)
-{
- int predictor, index, step;
- int nibble, nibble_count;
- unsigned char *input_end = input + BLOCK_SIZE;
-
-/* Get the chunk header */
- predictor = *input++ << 8;
- predictor |= *input++;
-
- index = predictor & 0x7f;
- if(index > 88) index = 88;
-
- predictor &= 0xff80;
- if(predictor & 0x8000) predictor -= 0x10000;
- step = ima4_step[index];
-
-/* Read the input buffer sequentially, one nibble at a time */
- nibble_count = 0;
- while(input < input_end)
- {
- nibble = nibble_count ? (*input++ >> 4) & 0x0f : *input & 0x0f;
-
- ima4_decode_sample(&predictor, &nibble, &index, &step);
- *output++ = predictor;
-
- nibble_count ^= 1;
- }
-}
-
-
-void ima4_encode_sample(int *last_sample, int *last_index, int *nibble, int next_sample)
-{
- int difference, new_difference, mask, step;
-
- difference = next_sample - *last_sample;
- *nibble = 0;
- step = ima4_step[*last_index];
- new_difference = step >> 3;
-
- if(difference < 0)
- {
- *nibble = 8;
- difference = -difference;
- }
-
- mask = 4;
- while(mask)
- {
- if(difference >= step)
- {
- *nibble |= mask;
- difference -= step;
- new_difference += step;
- }
-
- step >>= 1;
- mask >>= 1;
- }
-
- if(*nibble & 8)
- *last_sample -= new_difference;
- else
- *last_sample += new_difference;
-
- if(*last_sample > 32767) *last_sample = 32767;
- else
- if(*last_sample < -32767) *last_sample = -32767;
-
- *last_index += ima4_index[*nibble];
-
- if(*last_index < 0) *last_index = 0;
- else
- if(*last_index > 88) *last_index= 88;
-}
-
-void ima4_encode_block(quicktime_audio_map_t *atrack, unsigned char *output, int16_t *input, int step, int channel)
-{
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
- int i, nibble_count = 0, nibble, header;
-
-/* Get a fake starting sample */
- header = codec->last_samples[channel];
-/* Force rounding. */
- if(header < 0x7fc0) header += 0x40;
- if(header < 0) header += 0x10000;
- header &= 0xff80;
- *output++ = (header & 0xff00) >> 8;
- *output++ = (header & 0x80) + (codec->last_indexes[channel] & 0x7f);
-
- for(i = 0; i < SAMPLES_PER_BLOCK; i++)
- {
- ima4_encode_sample(&(codec->last_samples[channel]),
- &(codec->last_indexes[channel]),
- &nibble,
- *input);
-
- if(nibble_count)
- *output++ |= (nibble << 4);
- else
- *output = nibble;
-
- input += step;
- nibble_count ^= 1;
- }
-}
-
-/* Convert the number of samples in a chunk into the number of bytes in that */
-/* chunk. The number of samples in a chunk should end on a block boundary. */
-long ima4_samples_to_bytes(long samples, int channels)
-{
- long bytes = samples / SAMPLES_PER_BLOCK * BLOCK_SIZE * channels;
- return bytes;
-}
-
-/* Decode the chunk into the work buffer */
-int ima4_decode_chunk(quicktime_t *file, int track, long chunk, int channel)
-{
- int result = 0;
- int i, j;
- long chunk_samples, chunk_bytes;
- unsigned char *block_ptr;
- quicktime_trak_t *trak = file->atracks[track].track;
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)file->atracks[track].codec)->priv;
-
-/* Get the byte count to read. */
- chunk_samples = quicktime_chunk_samples(trak, chunk);
- chunk_bytes = ima4_samples_to_bytes(chunk_samples, file->atracks[track].channels);
-
-/* Get the buffer to read into. */
- if(codec->work_buffer && codec->work_size < chunk_samples)
- {
- free(codec->work_buffer);
- codec->work_buffer = 0;
- }
-
- if(!codec->work_buffer)
- {
- codec->work_size = chunk_samples;
- codec->work_buffer = malloc(sizeof(int16_t) * codec->work_size);
- }
-
- if(codec->read_buffer && codec->read_size < chunk_bytes)
- {
- free(codec->read_buffer);
- codec->read_buffer = 0;
- }
-
- if(!codec->read_buffer)
- {
- codec->read_size = chunk_bytes;
- codec->read_buffer = malloc(codec->read_size);
- }
-
-/* codec->work_size now holds the number of samples in the last chunk */
-/* codec->read_size now holds number of bytes in the last read buffer */
-
-/* Read the entire chunk regardless of where the desired sample range starts. */
- result = quicktime_read_chunk(file, (char*)codec->read_buffer,
- track, chunk, 0, chunk_bytes);
-
-/* Now decode the chunk, one block at a time, until the total samples in the chunk */
-/* is reached. */
-
- if(!result)
- {
- block_ptr = codec->read_buffer;
- for(i = 0; i < chunk_samples; i += SAMPLES_PER_BLOCK)
- {
- for(j = 0; j < file->atracks[track].channels; j++)
- {
- if(j == channel)
- ima4_decode_block(&(file->atracks[track]), &(codec->work_buffer[i]), block_ptr);
-
- block_ptr += BLOCK_SIZE;
- }
- }
- }
- codec->buffer_channel = channel;
- codec->chunk = chunk;
-
- return result;
-}
-
-
-/* =================================== public for ima4 */
-
-static void delete_codec(quicktime_audio_map_t *atrack)
-{
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
-
- if(codec->work_buffer) free(codec->work_buffer);
- if(codec->read_buffer) free(codec->read_buffer);
- if(codec->last_samples) free(codec->last_samples);
- if(codec->last_indexes) free(codec->last_indexes);
- codec->last_samples = 0;
- codec->last_indexes = 0;
- codec->read_buffer = 0;
- codec->work_buffer = 0;
- codec->chunk = 0;
- codec->buffer_channel = 0; /* Channel of work buffer */
- codec->work_size = 0; /* Size of work buffer */
- codec->read_size = 0;
- free(codec);
-}
-
-static int decode(quicktime_t *file,
- int16_t *output_i,
- float *output_f,
- long samples,
- int track,
- int channel)
-{
- int result = 0;
- int64_t chunk, chunk_sample, chunk_samples;
- int64_t i, chunk_start, chunk_end;
- quicktime_trak_t *trak = file->atracks[track].track;
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)file->atracks[track].codec)->priv;
-
-/* Get the first chunk with this routine and then increase the chunk number. */
- quicktime_chunk_of_sample(&chunk_sample, &chunk, trak, file->atracks[track].current_position);
-
-/* Read chunks and extract ranges of samples until the output is full. */
- for(i = 0; i < samples && !result; )
- {
-/* Get chunk we're on. */
- chunk_samples = quicktime_chunk_samples(trak, chunk);
-
- if(!codec->work_buffer ||
- codec->chunk != chunk ||
- codec->buffer_channel != channel)
- {
-/* read a new chunk if necessary */
- result = ima4_decode_chunk(file, track, chunk, channel);
- }
-
-/* Get boundaries from the chunk */
- chunk_start = 0;
- if(chunk_sample < file->atracks[track].current_position)
- chunk_start = file->atracks[track].current_position - chunk_sample;
-
- chunk_end = chunk_samples;
- if(chunk_sample + chunk_end > file->atracks[track].current_position + samples)
- chunk_end = file->atracks[track].current_position + samples - chunk_sample;
-
-/* Read from the chunk */
- if(output_i)
- {
-/*printf("decode_ima4 1 chunk %ld %ld-%ld output %ld\n", chunk, chunk_start + chunk_sample, chunk_end + chunk_sample, i); */
- while(chunk_start < chunk_end)
- {
- output_i[i++] = codec->work_buffer[chunk_start++];
- }
-/*printf("decode_ima4 2\n"); */
- }
- else
- if(output_f)
- {
- while(chunk_start < chunk_end)
- {
- output_f[i++] = (float)codec->work_buffer[chunk_start++] / 32767;
- }
- }
-
- chunk++;
- chunk_sample += chunk_samples;
- }
-
- return result;
-}
-
-static int encode(quicktime_t *file,
- int16_t **input_i,
- float **input_f,
- int track,
- long samples)
-{
- int result = 0;
- int64_t i, j, step;
- int64_t chunk_bytes;
- int64_t overflow_start;
- int64_t chunk_samples; /* Samples in the current chunk to be written */
- quicktime_audio_map_t *track_map = &(file->atracks[track]);
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)track_map->codec)->priv;
- quicktime_trak_t *trak = track_map->track;
- int16_t *input_ptr;
- unsigned char *output_ptr;
- quicktime_atom_t chunk_atom;
-
-/* Get buffer sizes */
- if(codec->work_buffer && codec->work_size < (samples + codec->work_overflow + 1) * track_map->channels)
- {
-/* Create new buffer */
- int64_t new_size = (samples + codec->work_overflow + 1) * track_map->channels;
- int16_t *new_buffer = malloc(sizeof(int16_t) * new_size);
-
-/* Copy overflow */
- for(i = 0; i < codec->work_overflow * track_map->channels; i++)
- new_buffer[i] = codec->work_buffer[i];
-
-/* Swap pointers. */
- free(codec->work_buffer);
- codec->work_buffer = new_buffer;
- codec->work_size = new_size;
- }
- else
- if(!codec->work_buffer)
- {
-/* No buffer in the first place. */
- codec->work_size = (samples + codec->work_overflow) * track_map->channels;
-/* Make the allocation enough for at least the flush routine. */
- if(codec->work_size < SAMPLES_PER_BLOCK * track_map->channels)
- codec->work_size = SAMPLES_PER_BLOCK * track_map->channels;
- codec->work_buffer = malloc(sizeof(int16_t) * codec->work_size);
- }
-
-/* Get output size */
- chunk_bytes = ima4_samples_to_bytes(samples + codec->work_overflow, track_map->channels);
- if(codec->read_buffer && codec->read_size < chunk_bytes)
- {
- free(codec->read_buffer);
- codec->read_buffer = 0;
- }
-
- if(!codec->read_buffer)
- {
- codec->read_buffer = malloc(chunk_bytes);
- codec->read_size = chunk_bytes;
- }
-
- if(!codec->last_samples)
- {
- codec->last_samples = malloc(sizeof(int) * track_map->channels);
- for(i = 0; i < track_map->channels; i++)
- {
- codec->last_samples[i] = 0;
- }
- }
-
- if(!codec->last_indexes)
- {
- codec->last_indexes = malloc(sizeof(int) * track_map->channels);
- for(i = 0; i < track_map->channels; i++)
- {
- codec->last_indexes[i] = 0;
- }
- }
-
-/* Arm the input buffer after the last overflow */
- step = track_map->channels;
- for(j = 0; j < track_map->channels; j++)
- {
- input_ptr = codec->work_buffer + codec->work_overflow * track_map->channels + j;
-
- if(input_i)
- {
- for(i = 0; i < samples; i++)
- {
- *input_ptr = input_i[j][i];
- input_ptr += step;
- }
- }
- else
- if(input_f)
- {
- for(i = 0; i < samples; i++)
- {
- *input_ptr = (int16_t)(input_f[j][i] * 32767);
- input_ptr += step;
- }
- }
- }
-
-/* Encode from the input buffer to the read_buffer up to a multiple of */
-/* blocks. */
- input_ptr = codec->work_buffer;
- output_ptr = codec->read_buffer;
-
- for(i = 0;
- i + SAMPLES_PER_BLOCK <= samples + codec->work_overflow;
- i += SAMPLES_PER_BLOCK)
- {
- for(j = 0; j < track_map->channels; j++)
- {
- ima4_encode_block(track_map, output_ptr, input_ptr + j, track_map->channels, j);
-
- output_ptr += BLOCK_SIZE;
- }
- input_ptr += SAMPLES_PER_BLOCK * track_map->channels;
- }
-
-/* Write to disk */
- chunk_samples = (int64_t)((samples + codec->work_overflow) / SAMPLES_PER_BLOCK) * SAMPLES_PER_BLOCK;
-
-/*printf("quicktime_encode_ima4 1 %ld\n", chunk_samples); */
-/* The block division may result in 0 samples getting encoded. */
-/* Don't write 0 samples. */
- if(chunk_samples)
- {
- quicktime_write_chunk_header(file, trak, &chunk_atom);
- result = quicktime_write_data(file, (char*)codec->read_buffer, chunk_bytes);
- quicktime_write_chunk_footer(file,
- trak,
- track_map->current_chunk,
- &chunk_atom,
- chunk_samples);
-
- if(result)
- result = 0;
- else
- result = 1; /* defeat fwrite's return */
-
- track_map->current_chunk++;
- }
-
-/* Move the last overflow to the front */
- overflow_start = i;
- input_ptr = codec->work_buffer;
- for(i = overflow_start * track_map->channels ;
- i < (samples + codec->work_overflow) * track_map->channels;
- i++)
- {
- *input_ptr++ = codec->work_buffer[i];
- }
- codec->work_overflow = samples + codec->work_overflow - overflow_start;
-
- return result;
-}
-
-void flush(quicktime_t *file, int track)
-{
- quicktime_audio_map_t *track_map = &(file->atracks[track]);
- quicktime_ima4_codec_t *codec = ((quicktime_codec_t*)track_map->codec)->priv;
- int i;
-
-/*printf("quicktime_flush_ima4 %ld\n", codec->work_overflow); */
- if(codec->work_overflow)
- {
-/* Zero out enough to get a block */
- i = codec->work_overflow * track_map->channels;
- while(i < SAMPLES_PER_BLOCK * track_map->channels)
- {
- codec->work_buffer[i++] = 0;
- }
- codec->work_overflow = i / track_map->channels + 1;
-/* Write the work_overflow only. */
- encode(file, 0, 0, track, 0);
- }
-}
-
-void quicktime_init_codec_ima4(quicktime_audio_map_t *atrack)
-{
- quicktime_codec_t *codec_base = (quicktime_codec_t*)atrack->codec;
-// quicktime_ima4_codec_t *codec = codec_base->priv;
-
-/* Init public items */
- codec_base->priv = calloc(1, sizeof(quicktime_ima4_codec_t));
- codec_base->delete_acodec = delete_codec;
- codec_base->decode_video = 0;
- codec_base->encode_video = 0;
- codec_base->decode_audio = decode;
- codec_base->encode_audio = encode;
- codec_base->flush = flush;
- codec_base->fourcc = QUICKTIME_IMA4;
- codec_base->title = "IMA 4";
- codec_base->desc = "IMA 4";
- codec_base->wav_id = 0x11;
-
-/* Init private items */
-}
projects / goodguy / history.git / blobdiff