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Commit c6cf8e0c authored by Dominik Loidolt's avatar Dominik Loidolt
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add STUFF mode decompression 

remove setup->max_stream_len assume now that the max cw_len is always 32 bits
add a input parameter check for the rice_decoder() function
change input parameter check for get_n_bits32() function
parent 11f472d0
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1 merge request!11decompression/compression for non-imagette data
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with 58 additions and 22 deletions
lib/decmp.c
+ 58
− 22
View file @ c6cf8e0c
......@@ -32,6 +32,8 @@
#include "cmp_entity.h"
#define MAX_CW_LEN 32 /* maximum Golomb code word bit length */
/* maximum used bits registry */
extern struct cmp_max_used_bits max_used_bits;
......@@ -45,7 +47,6 @@ struct decoder_setup {
const struct decoder_setup *setup); /* pointer to the decoding function */
uint32_t *bitstream_adr; /* start address of the compressed data bitstream */
uint32_t max_stream_len; /* maximum length of the bitstream/icu_output_buf in bits */
uint32_t max_cw_len; /* TODO */
uint32_t encoder_par1; /* encoding parameter 1 */
uint32_t encoder_par2; /* encoding parameter 2 */
uint32_t outlier_par; /* outlier parameter */
......@@ -93,8 +94,8 @@ static unsigned int count_leading_ones(uint32_t value)
* 0 on failure
*/
static int rice_decoder(uint32_t code_word, unsigned int m,
unsigned int log2_m, unsigned int *decoded_cw)
static int rice_decoder(uint32_t code_word, unsigned int m, unsigned int log2_m,
unsigned int *decoded_cw)
{
unsigned int q; /* quotient code */
unsigned int ql; /* length of the quotient code */
......@@ -104,6 +105,9 @@ static int rice_decoder(uint32_t code_word, unsigned int m,
(void)m; /* we don't need the Golomb parameter */
if (log2_m > 32)
return 0;
q = count_leading_ones(code_word); /* decode unary coding */
ql = q + 1; /* Number of 1's + following 0 */
......@@ -124,7 +128,7 @@ static int rice_decoder(uint32_t code_word, unsigned int m,
else
r = code_word >> (32 - rl);
*decoded_cw = (q << log2_m) + r;
*decoded_cw = (q << rl) + r;
return cw_len;
}
......@@ -206,16 +210,15 @@ static decoder_ptr select_decoder(unsigned int golomb_par)
/**
* @brief read a value of up to 32 bits from a bitstream
*
* @param p_value pointer to the read value (can be NULL), the
* @param p_value pointer to the read value, the
* read value will be converted to the system
* endianness
* @param n_bits number of bits to read from the bitstream
* @param bit_offset bit index where the bits will be read, seen from
* the very beginning of the bitstream
* @param bitstream_adr this is the pointer to the beginning of the
* bitstream (can be NULL)
* @param max_stream_len maximum length of the bitstream in bits; is
* ignored if bitstream_adr is NULL
* bitstream
* @param max_stream_len maximum length of the bitstream in bits *
*
* @returns bit position of the last read bit in the bitstream on success;
* returns negative in case of erroneous input; returns CMP_ERROR_SMALL_BUF
......@@ -238,12 +241,10 @@ static int get_n_bits32(uint32_t *p_value, unsigned int n_bits, int bit_offset,
return -1;
if (n_bits > 32)
return -1;
/* nothing to read */
if (!bitstream_adr)
return stream_len;
return -1;
if (!p_value)
return stream_len;
return -1;
/* Check if bitstream buffer is large enough */
if ((unsigned int)stream_len > max_stream_len) {
......@@ -310,10 +311,10 @@ static int decode_normal(uint32_t *decoded_value, int stream_pos,
/* check if we can read max_cw_len or less; we do not now how long the
* code word actually is so we try to read the maximum cw length */
if ((unsigned int)stream_pos + setup->max_cw_len > setup->max_stream_len)
if ((unsigned int)stream_pos + 32 > setup->max_stream_len)
n_read_bits = setup->max_stream_len - (unsigned int)stream_pos;
else
n_read_bits = setup->max_cw_len;
n_read_bits = MAX_CW_LEN;
stream_pos_read = get_n_bits32(&read_val, n_read_bits, stream_pos,
setup->bitstream_adr, setup->max_stream_len);
......@@ -410,13 +411,37 @@ static int decode_multi(uint32_t *decoded_value, int stream_pos,
stream_pos = get_n_bits32(&unencoded_val, unencoded_len, stream_pos,
setup->bitstream_adr, setup->max_stream_len);
if (stream_pos >= 0)
*decoded_value = unencoded_val + setup->outlier_par;
}
return stream_pos;
}
/**
* @brief get the value unencoded with setup->cmp_par_1 bits without any
* additional changes from the bitstream
*
* @param decoded_value pointer to the decoded value
* @param stream_pos start bit position code word to be decoded in the bitstream
* @param setup pointer to the decoder setup
*
* @returns bit index of the next code word in the bitstream on success; returns
* negative in case of erroneous input; returns CMP_ERROR_SMALL_BUF if the
* bitstream buffer is too small to read the value from the bitstream
*
*/
static int decode_none(uint32_t *decoded_value, int stream_pos,
const struct decoder_setup *setup)
{
stream_pos = get_n_bits32(decoded_value, setup->encoder_par1, stream_pos,
setup->bitstream_adr, setup->max_stream_len);
return stream_pos;
}
/**
* @brief remap a unsigned value back to a signed value
* @note this is the reverse function of map_to_pos()
......@@ -461,11 +486,14 @@ static int decode_value(uint32_t *decoded_value, uint32_t model,
if (stream_pos <= 0)
return stream_pos;
if (setup->decode_method_f == decode_none) /* we are done here in stuff mode */
return stream_pos;
*decoded_value = re_map_to_pos(*decoded_value);
*decoded_value += round_fwd(model, setup->lossy_par);
*decoded_value &= mask;
*decoded_value &= mask; /* TODO: why?? */
*decoded_value = round_inv(*decoded_value, setup->lossy_par);
......@@ -482,7 +510,10 @@ static int configure_decoder_setup(struct decoder_setup *setup,
setup->decode_method_f = &decode_multi;
else if (zero_escape_mech_is_used(cfg->cmp_mode))
setup->decode_method_f = &decode_zero;
else if (cfg->cmp_mode == CMP_MODE_STUFF)
setup->decode_method_f = &decode_none;
else {
setup->decode_method_f = NULL;
debug_print("Error: Compression mode not supported.\n");
return -1;
}
......@@ -493,11 +524,9 @@ static int configure_decoder_setup(struct decoder_setup *setup,
return -1;
}
setup->max_stream_len = (cfg->buffer_length) * CHAR_BIT; /* maximum length of the bitstream/icu_output_buf in bits */
if (rdcu_supported_data_type_is_used(cfg->data_type))
setup->max_cw_len = 16;
else
setup->max_cw_len = 32;
setup->encoder_par1 = cmp_par; /* encoding parameter 1 */
if (ilog_2(cmp_par) < 0)
return -1;
setup->encoder_par2 = ilog_2(cmp_par); /* encoding parameter 2 */
setup->outlier_par = spill; /* outlier parameter */
setup->lossy_par = lossy_par; /* lossy compression parameter */
......@@ -1708,6 +1737,12 @@ static int decompress_l_fx_efx_ncob_ecob(const struct cmp_cfg *cfg)
cfg->model_value, setup_ncob.lossy_par);
up_model_buf[i].ncob_y = cmp_up_model(data_buf[i].ncob_y, model.ncob_y,
cfg->model_value, setup_ncob.lossy_par);
up_model_buf[i].efx = cmp_up_model(data_buf[i].efx, model.efx,
cfg->model_value, setup_efx.lossy_par);
up_model_buf[i].ecob_x = cmp_up_model(data_buf[i].ecob_x, model.ecob_x,
cfg->model_value, setup_ecob.lossy_par);
up_model_buf[i].ecob_y = cmp_up_model(data_buf[i].ecob_y, model.ecob_y,
cfg->model_value, setup_ecob.lossy_par);
up_model_buf[i].fx_variance = cmp_up_model(data_buf[i].fx_variance, model.fx_variance,
cfg->model_value, setup_fx_var.lossy_par);
up_model_buf[i].cob_x_variance = cmp_up_model(data_buf[i].cob_x_variance, model.cob_x_variance,
......@@ -1968,7 +2003,8 @@ static int decompressed_data_internal(struct cmp_cfg *cfg)
int data_size, strem_len_bit = -1;
if (!cfg)
return 0; /* or -1? */
return -1;
if (!cfg->icu_output_buf)
return -1;
......
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