static uint32_t get_preroll_samples
(
libavsmash_audio_decode_handler_t *adhp,
uint64_t skip_decoded_samples,
uint32_t *frame_number
)
{
/* Some audio CODEC requires pre-roll for correct composition. */
lsmash_sample_property_t prop;
if( lsmash_get_sample_property_from_media_timeline( adhp->root, adhp->track_ID, *frame_number, &prop ) )
return 0;
if( prop.pre_roll.distance == 0 )
{
if( skip_decoded_samples == 0 || !adhp->implicit_preroll )
return 0;
/* Estimate pre-roll distance. */
for( uint32_t i = 1; i <= adhp->frame_count || skip_decoded_samples; i++ )
{
libavsmash_summary_t *dummy = NULL;
uint32_t frame_length;
if( get_frame_length( adhp, i, &frame_length, &dummy ) )
break;
if( skip_decoded_samples < frame_length )
skip_decoded_samples = 0;
else
skip_decoded_samples -= frame_length;
++ prop.pre_roll.distance;
}
}
uint32_t preroll_samples = 0;
for( uint32_t i = 0; i < prop.pre_roll.distance; i++ )
{
if( *frame_number > 1 )
--(*frame_number);
else
break;
libavsmash_summary_t *dummy = NULL;
uint32_t frame_length;
if( get_frame_length( adhp, *frame_number, &frame_length, &dummy ) )
break;
preroll_samples += frame_length;
}
return preroll_samples;
}
static int find_start_audio_frame
(
libavsmash_audio_decode_handler_t *adhp,
int output_sample_rate,
uint64_t skip_decoded_samples,
uint64_t start_frame_pos,
uint64_t *start_offset
)
{
uint32_t frame_number = 1;
uint64_t current_frame_pos = 0;
uint64_t next_frame_pos = 0;
int current_sample_rate = 0;
uint32_t current_frame_length = 0;
uint64_t pcm_sample_count = 0; /* the number of accumulated PCM samples before resampling per sequence */
uint64_t resampled_sample_count = 0; /* the number of accumulated PCM samples after resampling per sequence */
uint64_t prior_sequences_resampled_count = 0; /* the number of accumulated PCM samples of all prior sequences */
do
{
current_frame_pos = next_frame_pos;
libavsmash_summary_t *s = NULL;
uint32_t frame_length;
if( get_frame_length( adhp, frame_number, &frame_length, &s ) )
{
++frame_number;
continue;
}
if( (current_sample_rate != s->extended.sample_rate && s->extended.sample_rate > 0)
|| current_frame_length != frame_length )
{
/* Encountered a new sequence. */
prior_sequences_resampled_count += resampled_sample_count;
pcm_sample_count = 0;
current_sample_rate = s->extended.sample_rate > 0 ? s->extended.sample_rate : adhp->config.ctx->sample_rate;
current_frame_length = frame_length;
}
pcm_sample_count += frame_length;
resampled_sample_count = output_sample_rate == current_sample_rate || pcm_sample_count == 0
? pcm_sample_count
: RESAMPLE_PCM_COUNT( pcm_sample_count );
next_frame_pos = prior_sequences_resampled_count + resampled_sample_count;
if( start_frame_pos < next_frame_pos )
break;
++frame_number;
} while( frame_number <= adhp->frame_count );
*start_offset = start_frame_pos - current_frame_pos;
if( *start_offset && current_sample_rate != output_sample_rate )
/* start_offset is applied at the decoder sampling rate. */
*start_offset = (*start_offset * current_sample_rate - 1) / output_sample_rate + 1;
*start_offset += get_preroll_samples( adhp, skip_decoded_samples, &frame_number );
return frame_number;
}
static int bu92747_get_frame_length(struct bu92747_port *s)
{
struct rev_frame_length *f = &(s->rev_frames);
unsigned long len = 0;
#if 0
wait_event_interruptible_timeout(s->data_ready_wq,
atomic_read(&(s->data_ready) ),
msecs_to_jiffies(1000) );
if ( 0 == atomic_read(&(s->data_ready)) ) {
printk("waiting 'data_ready_wq' timed out.");
return -1;
}
#endif
spin_lock(&s->data_lock);
if (get_frame_length(f, &len) != 0) {
printk("line %d: FIR data not ready......\n", __LINE__);
//atomic_set(&(s->data_ready), 0);
}
spin_unlock(&s->data_lock);
return len;
}