/** Calculate actual (or really close to actual) bitcost for coding coefficients
* \param coeff coefficient array
* \param width coeff block width
* \param type data type (0 == luma)
* \returns bits needed to code input coefficients
*/
int32_t kvz_get_coeff_cost(const encoder_state_t * const state, coeff_t *coeff, int32_t width, int32_t type, int8_t scan_mode)
{
int32_t cost = 0;
int i;
int found = 0;
encoder_state_t state_copy;
// Make sure there are coeffs present
for(i = 0; i < width*width; i++) {
if (coeff[i] != 0) {
found = 1;
break;
}
}
if(!found) return 0;
// Store cabac state and contexts
memcpy(&state_copy,state,sizeof(encoder_state_t));
// Clear bytes and bits and set mode to "count"
state_copy.cabac.only_count = 1;
state_copy.cabac.num_buffered_bytes = 0;
state_copy.cabac.bits_left = 23;
// Execute the coding function
kvz_encode_coeff_nxn(&state_copy, coeff, width, type, scan_mode, 0);
// Store bitcost before restoring cabac
cost = (23-state_copy.cabac.bits_left) + (state_copy.cabac.num_buffered_bytes << 3);
return cost;
}
/**
* \brief Calculate actual (or really close to actual) bitcost for coding
* coefficients.
*
* \param coeff coefficient array
* \param width coeff block width
* \param type data type (0 == luma)
*
* \returns bits needed to code input coefficients
*/
static INLINE uint32_t get_coeff_cabac_cost(
const encoder_state_t * const state,
const coeff_t *coeff,
int32_t width,
int32_t type,
int8_t scan_mode)
{
// Make sure there are coeffs present
bool found = false;
for (int i = 0; i < width*width; i++) {
if (coeff[i] != 0) {
found = 1;
break;
}
}
if (!found) return 0;
// Take a copy of the CABAC so that we don't overwrite the contexts when
// counting the bits.
cabac_data_t cabac_copy;
memcpy(&cabac_copy, &state->cabac, sizeof(cabac_copy));
// Clear bytes and bits and set mode to "count"
cabac_copy.only_count = 1;
cabac_copy.num_buffered_bytes = 0;
cabac_copy.bits_left = 23;
// Execute the coding function.
// It is safe to drop the const modifier since state won't be modified
// when cabac.only_count is set.
kvz_encode_coeff_nxn((encoder_state_t*) state,
&cabac_copy,
coeff,
width,
type,
scan_mode,
0);
return (23 - cabac_copy.bits_left) + (cabac_copy.num_buffered_bytes << 3);
}
