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adpcmdec: complete ima adpcm support.

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This commit is contained in:
Michael Smith 2009-07-23 16:13:28 -07:00
parent e90934dab3
commit 29c3542dd5
1 changed files with 49 additions and 48 deletions
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97
gst/adpcmdec/adpcmdec.c
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@ -95,6 +95,7 @@ typedef struct _ADPCMDec
gboolean is_setup;
GstClockTime timestamp;
GstClockTime base_timestamp;
guint64 out_samples;
@ -120,11 +121,11 @@ adpcmdec_setup (ADPCMDec * dec)
dec->is_setup = TRUE;
dec->timestamp = GST_CLOCK_TIME_NONE;
dec->base_timestamp = GST_CLOCK_TIME_NONE;
dec->adapter = gst_adapter_new ();
dec->out_samples = 0;
return gst_pad_push_event (dec->srcpad, gst_event_new_new_segment (FALSE,
1.0, GST_FORMAT_TIME, 0, -1, 0));
return TRUE;
}
static void
@ -301,10 +302,8 @@ adpcmdec_decode_ms_block (ADPCMDec * dec, int n_samples, guint8 * data,
return TRUE;
}
static int ima_indx_adjust[16] = { -1, -1, -1, -1, /* +0 - +3, decrease the step size */
2, 4, 6, 8, /* +4 - +7, increase the step size */
-1, -1, -1, -1, /* -0 - -3, decrease the step size */
2, 4, 6, 8, /* -4 - -7, increase the step size */
static int ima_indx_adjust[16] = {
-1, -1, -1, -1, 2, 4, 6, 8, -1, -1, -1, -1, 2, 4, 6, 8,
};
static int ima_step_size[89] = {
@ -328,8 +327,14 @@ adpcmdec_decode_ima_block (ADPCMDec * dec, int n_samples, guint8 * data,
{
gint16 stepindex[2];
int channel;
int idx; /* Current byte offset in 'data' */
int i; /* Current sample */
int idx;
int i, j;
int sample;
if ((n_samples - dec->channels) % 8 != 0) {
GST_WARNING_OBJECT (dec, "Input not correct size");
return FALSE;
}
for (channel = 0; channel < dec->channels; channel++) {
samples[channel] = read_sample (data + channel * 4);
@ -344,45 +349,34 @@ adpcmdec_decode_ima_block (ADPCMDec * dec, int n_samples, guint8 * data,
i = dec->channels;
idx = 4 * dec->channels;
GST_DEBUG ("Decoding %d samples", n_samples);
for (; i < n_samples; i++) {
int chan = i % dec->channels;
int bytecode;
int step;
int val;
int difference;
while (i < n_samples) {
for (channel = 0; channel < dec->channels; channel++) {
sample = i + channel;
for (j = 0; j < 8; j++) {
int bytecode;
int step;
int diff;
#if 1
if (i % 2 == 0) {
bytecode = (data[idx] >> 4) & 0x0F;
} else {
bytecode = data[idx] & 0x0F;
idx++;
if (j % 2 == 0) {
bytecode = data[idx] & 0x0F;
} else {
bytecode = (data[idx] >> 4) & 0x0F;
idx++;
}
step = ima_step_size[stepindex[channel]];
diff = (2 * (bytecode & 0x7) * step + step) / 8;
if (bytecode & 8)
diff = -diff;
samples[sample] =
CLAMP (samples[sample - dec->channels] + diff, G_MININT16,
G_MAXINT16);
stepindex[channel] =
CLAMP (stepindex[channel] + ima_indx_adjust[bytecode], 0, 88);
sample += dec->channels;
}
}
#endif
step = ima_step_size[stepindex[chan]];
#if 1
difference = (2 * (bytecode & 0x7) * step + step) / 8;
if (bytecode & 8)
difference = -difference;
#else
val = step >> 3;
if (bytecode & 4)
val += step;
if (bytecode & 2)
val += step >> 1;
if (bytecode & 1)
val += step >> 2;
if (bytecode & 8)
val = -val;
difference = val;
#endif
val = (int) samples[i - dec->channels] + difference;
samples[i] = CLAMP (val, G_MININT16, G_MAXINT16);
stepindex[channel] = CLAMP (stepindex[channel] + ima_indx_adjust[bytecode],
0, 88);
i += 8 * dec->channels;
}
return TRUE;
}
@ -402,8 +396,12 @@ adpcmdec_chain (GstPad * pad, GstBuffer * buf)
if (!dec->is_setup)
adpcmdec_setup (dec);
if (dec->timestamp == GST_CLOCK_TIME_NONE)
dec->timestamp = GST_BUFFER_TIMESTAMP (buf);
if (dec->base_timestamp == GST_CLOCK_TIME_NONE) {
dec->base_timestamp = GST_BUFFER_TIMESTAMP (buf);
if (dec->base_timestamp == GST_CLOCK_TIME_NONE)
dec->base_timestamp = 0;
dec->timestamp = dec->base_timestamp;
}
gst_adapter_push (dec->adapter, buf);
@ -449,7 +447,7 @@ adpcmdec_chain (GstPad * pad, GstBuffer * buf)
gst_buffer_set_caps (outbuf, dec->output_caps);
GST_BUFFER_TIMESTAMP (outbuf) = dec->timestamp;
dec->out_samples += samples / dec->channels;
dec->timestamp =
dec->timestamp = dec->base_timestamp +
gst_util_uint64_scale_int (dec->out_samples, GST_SECOND, dec->rate);
GST_BUFFER_DURATION (outbuf) =
dec->timestamp - GST_BUFFER_TIMESTAMP (outbuf);
@ -472,6 +470,9 @@ adpcmdec_sink_event (GstPad * pad, GstEvent * event)
gboolean res;
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_STOP:
dec->out_samples = 0;
dec->timestamp = GST_CLOCK_TIME_NONE;
dec->base_timestamp = GST_CLOCK_TIME_NONE;
gst_adapter_clear (dec->adapter);
/* Fall through */
default: