static int fetch(extrapolater_t *self, unsigned nframes)
{
const pcm_sample_description_t *sfmt = pcm_get_format(self->src);
buffer_t *bp = &self->buffer[self->nbuffer];
int rc = 0;
if (realloc_buffer(bp, nframes * sfmt->bytes_per_frame) == 0) {
rc = pcm_read_frames(self->src, bp->data, nframes);
bp->count = rc > 0 ? rc : 0;
}
if (rc > 0)
self->nbuffer ^= 1;
return bp->count;
}
static int read_frames(pcm_reader_t *reader, void *buffer, unsigned nframes)
{
pcm_float_converter_t *self = (pcm_float_converter_t *)reader;
const pcm_sample_description_t *sfmt = pcm_get_format(self->src);
nframes = pcm_read_frames(self->src, buffer, nframes);
if (!(sfmt->sample_type & PCM_TYPE_FLOAT)) {
int32_t *ip = buffer;
float *op = buffer;
unsigned i, count = nframes * sfmt->channels_per_frame;
for (i = 0; i < count; ++i)
op[i] = ip[i] / 2147483648.0f;
}
return nframes;
}
static
int encode(aacenc_param_ex_t *params, pcm_reader_t *reader,
HANDLE_AACENCODER encoder, uint32_t frame_length,
m4af_ctx_t *m4af)
{
int16_t *ibuf = 0, *ip;
aacenc_frame_t obuf[2] = {{ 0 }}, *obp;
unsigned flip = 0;
int nread = 1;
int rc = -1;
int remaining, consumed;
int frames_written = 0, encoded = 0;
aacenc_progress_t progress = { 0 };
const pcm_sample_description_t *fmt = pcm_get_format(reader);
ibuf = malloc(frame_length * fmt->bytes_per_frame);
aacenc_progress_init(&progress, pcm_get_length(reader), fmt->sample_rate);
for (;;) {
/*
* Since we delay the write, we cannot just exit loop when interrupted.
* Instead, we regard it as EOF.
*/
if (g_interrupted)
nread = 0;
if (nread > 0) {
if ((nread = pcm_read_frames(reader, ibuf, frame_length)) < 0) {
fprintf(stderr, "ERROR: read failed\n");
goto END;
}
if (!params->silent)
aacenc_progress_update(&progress, pcm_get_position(reader),
fmt->sample_rate * 2);
}
ip = ibuf;
remaining = nread;
do {
obp = &obuf[flip];
consumed = aac_encode_frame(encoder, fmt, ip, remaining, obp);
if (consumed < 0) goto END;
if (consumed == 0 && obp->size == 0) goto DONE;
if (obp->size == 0) break;
remaining -= consumed;
ip += consumed * fmt->channels_per_frame;
flip ^= 1;
/*
* As we pad 1 frame at beginning and ending by our extrapolator,
* we want to drop them.
* We delay output by 1 frame by double buffering, and discard
* second frame and final frame from the encoder.
* Since sbr_header is included in the first frame (in case of
* SBR), we cannot discard first frame. So we pick second instead.
*/
++encoded;
if (encoded == 1 || encoded == 3)
continue;
obp = &obuf[flip];
if (write_sample(params->output_fp, m4af, obp) < 0)
goto END;
++frames_written;
} while (remaining > 0);
}
DONE:
if (!params->silent)
aacenc_progress_finish(&progress, pcm_get_position(reader));
rc = frames_written;
END:
if (ibuf) free(ibuf);
if (obuf[0].data) free(obuf[0].data);
if (obuf[1].data) free(obuf[1].data);
return rc;
}
static int read_frames(pcm_reader_t *reader, void *buffer, unsigned nframes)
{
limiter_t *self = (limiter_t *)reader;
unsigned i, n, res, nch = self->format.channels_per_frame;
size_t bytes = nframes * pcm_get_format(self->src)->bytes_per_frame;
buffer_t *ibp = &self->buffers[nch];
float *obp = buffer;
do {
if (reserve_buffer(ibp, bytes, 1) < 0)
return -1;
res = pcm_read_frames(self->src, ibp->data, nframes);
for (n = 0; n < nch; ++n) {
float *ip = (float *)ibp->data, *x;
buffer_t *bp = &self->buffers[n];
unsigned end, limit;
if (reserve_buffer(bp, bp->count + res, sizeof(float)) < 0)
return -1;
x = bp->data;
for (i = 0; i < res; ++i)
x[bp->count++] = pcm_clip(ip[i * nch + n], -3.0, 3.0);
limit = bp->count;
if (limit > 0 && res > 0) {
float last = x[limit - 1];
for (; limit > 0 && x[limit-1] * last > 0; --limit)
;
}
end = bp->head;
while (end < limit) {
unsigned start, peak_pos;
float peak;
for (peak_pos = end; peak_pos < limit; ++peak_pos)
if (x[peak_pos] > 1.0f || x[peak_pos] < -1.0f)
break;
if (peak_pos == limit)
break;
start = peak_pos;
peak = fabs(x[peak_pos]);
while (start > bp->head && x[peak_pos] * x[start] >= 0.0f)
--start;
++start;
for (end = peak_pos + 1; end < limit; ++end) {
float y;
if (x[peak_pos] * x[end] < 0.0f)
break;
y = fabs(x[end]);
if (y > peak) {
peak = y;
peak_pos = end;
}
}
if (peak < 2.0f) {
float a = (peak - 1.0f) / (peak * peak);
if (x[peak_pos] > 0.0f) a = -a;
for (i = start; i < end; ++i)
x[i] = x[i] + a * x[i] * x[i];
} else {
float u = peak, v = 1.0f;
float a = (u - 2.0f * v) / (u * u * u);
float b = (3.0f * v - 2.0f * u) / (u * u);
if (x[peak_pos] < 0.0f) b = -b;
for (i = start; i < end; ++i)
x[i] = x[i] + b * x[i] * x[i] + a * x[i] * x[i] * x[i];
}
}
bp->head = limit;
}
res = nframes;
for (n = 0; n < nch; ++n)
if (self->buffers[n].head < res)
res = self->buffers[n].head;
for (i = 0; i < res; ++i)
for (n = 0; n < nch; ++n)
*obp++ = ((float *)self->buffers[n].data)[i];
if (res) {
for (n = 0; n < nch; ++n) {
buffer_t *bp = &self->buffers[n];
float *p = bp->data;
memmove(p, p + res, (bp->count - res) * sizeof(float));
bp->count -= res;
bp->head -= res;
}
}
} while (res == 0 && self->buffers[0].count);
self->position += res;
return res;
}