Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

h261: cosmetics: Move functions to avoid forward declarations

Browse Source
pull/21/head
Diego Biurrun 12 years ago
parent b78f81c803
commit 0404ec619d
2 changed files with 161 additions and 166 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 178
      libavcodec/h261dec.c
  2. 149
      libavcodec/h261enc.c

178
libavcodec/h261dec.c
Unescape View File

@ -44,8 +44,6 @@ static VLC h261_mtype_vlc;
static VLC h261_mv_vlc;
static VLC h261_cbp_vlc;
static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded);
static av_cold void h261_decode_init_vlc(H261Context *h)
{
static int done = 0;
@ -246,6 +244,94 @@ static int decode_mv_component(GetBitContext *gb, int v)
return v;
}
/**
* Decode a macroblock.
* @return <0 if an error occurred
*/
static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
{
MpegEncContext *const s = &h->s;
int code, level, i, j, run;
RLTable *rl = &h261_rl_tcoeff;
const uint8_t *scan_table;
/* For the variable length encoding there are two code tables, one being
* used for the first transmitted LEVEL in INTER, INTER + MC and
* INTER + MC + FIL blocks, the second for all other LEVELs except the
* first one in INTRA blocks which is fixed length coded with 8 bits.
* NOTE: The two code tables only differ in one VLC so we handle that
* manually. */
scan_table = s->intra_scantable.permutated;
if (s->mb_intra) {
/* DC coef */
level = get_bits(&s->gb, 8);
// 0 (00000000b) and -128 (10000000b) are FORBIDDEN
if ((level & 0x7F) == 0) {
av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
level, s->mb_x, s->mb_y);
return -1;
}
/* The code 1000 0000 is not used, the reconstruction level of 1024
* being coded as 1111 1111. */
if (level == 255)
level = 128;
block[0] = level;
i = 1;
} else if (coded) {
// Run Level Code
// EOB Not possible for first level when cbp is available (that's why the table is different)
// 0 1 1s
// * * 0*
int check = show_bits(&s->gb, 2);
i = 0;
if (check & 0x2) {
skip_bits(&s->gb, 2);
block[0] = (check & 0x1) ? -1 : 1;
i = 1;
}
} else {
i = 0;
}
if (!coded) {
s->block_last_index[n] = i - 1;
return 0;
}
for (;;) {
code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
if (code < 0) {
av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
s->mb_x, s->mb_y);
return -1;
}
if (code == rl->n) {
/* escape */
/* The remaining combinations of (run, level) are encoded with a
* 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits
* level. */
run = get_bits(&s->gb, 6);
level = get_sbits(&s->gb, 8);
} else if (code == 0) {
break;
} else {
run = rl->table_run[code];
level = rl->table_level[code];
if (get_bits1(&s->gb))
level = -level;
}
i += run;
if (i >= 64) {
av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n",
s->mb_x, s->mb_y);
return -1;
}
j = scan_table[i];
block[j] = level;
i++;
}
s->block_last_index[n] = i - 1;
return 0;
}
static int h261_decode_mb(H261Context *h)
{
MpegEncContext *const s = &h->s;
@ -353,94 +439,6 @@ intra:
return SLICE_OK;
}
/**
* Decode a macroblock.
* @return <0 if an error occurred
*/
static int h261_decode_block(H261Context *h, int16_t *block, int n, int coded)
{
MpegEncContext *const s = &h->s;
int code, level, i, j, run;
RLTable *rl = &h261_rl_tcoeff;
const uint8_t *scan_table;
/* For the variable length encoding there are two code tables, one being
* used for the first transmitted LEVEL in INTER, INTER + MC and
* INTER + MC + FIL blocks, the second for all other LEVELs except the
* first one in INTRA blocks which is fixed length coded with 8 bits.
* NOTE: The two code tables only differ in one VLC so we handle that
* manually. */
scan_table = s->intra_scantable.permutated;
if (s->mb_intra) {
/* DC coef */
level = get_bits(&s->gb, 8);
// 0 (00000000b) and -128 (10000000b) are FORBIDDEN
if ((level & 0x7F) == 0) {
av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n",
level, s->mb_x, s->mb_y);
return -1;
}
/* The code 1000 0000 is not used, the reconstruction level of 1024
* being coded as 1111 1111. */
if (level == 255)
level = 128;
block[0] = level;
i = 1;
} else if (coded) {
// Run Level Code
// EOB Not possible for first level when cbp is available (that's why the table is different)
// 0 1 1s
// * * 0*
int check = show_bits(&s->gb, 2);
i = 0;
if (check & 0x2) {
skip_bits(&s->gb, 2);
block[0] = (check & 0x1) ? -1 : 1;
i = 1;
}
} else {
i = 0;
}
if (!coded) {
s->block_last_index[n] = i - 1;
return 0;
}
for (;;) {
code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
if (code < 0) {
av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n",
s->mb_x, s->mb_y);
return -1;
}
if (code == rl->n) {
/* escape */
/* The remaining combinations of (run, level) are encoded with a
* 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits
* level. */
run = get_bits(&s->gb, 6);
level = get_sbits(&s->gb, 8);
} else if (code == 0) {
break;
} else {
run = rl->table_run[code];
level = rl->table_level[code];
if (get_bits1(&s->gb))
level = -level;
}
i += run;
if (i >= 64) {
av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n",
s->mb_x, s->mb_y);
return -1;
}
j = scan_table[i];
block[j] = level;
i++;
}
s->block_last_index[n] = i - 1;
return 0;
}
/**
* Decode the H.261 picture header.
* @return <0 if no startcode found

149
libavcodec/h261enc.c
Unescape View File

@ -31,9 +31,6 @@
#include "h261.h"
#include "h261data.h"
static void h261_encode_block(H261Context *h, int16_t *block,
int n);
int ff_h261_get_picture_format(int width, int height)
{
// QCIF
@ -155,6 +152,79 @@ static inline int get_cbp(MpegEncContext *s, int16_t block[6][64])
return cbp;
}
/**
* Encode an 8x8 block.
* @param block the 8x8 block
* @param n block index (0-3 are luma, 4-5 are chroma)
*/
static void h261_encode_block(H261Context *h, int16_t *block, int n)
{
MpegEncContext *const s = &h->s;
int level, run, i, j, last_index, last_non_zero, sign, slevel, code;
RLTable *rl;
rl = &h261_rl_tcoeff;
if (s->mb_intra) {
/* DC coef */
level = block[0];
/* 255 cannot be represented, so we clamp */
if (level > 254) {
level = 254;
block[0] = 254;
}
/* 0 cannot be represented also */
else if (level < 1) {
level = 1;
block[0] = 1;
}
if (level == 128)
put_bits(&s->pb, 8, 0xff);
else
put_bits(&s->pb, 8, level);
i = 1;
} else if ((block[0] == 1 || block[0] == -1) &&
(s->block_last_index[n] > -1)) {
// special case
put_bits(&s->pb, 2, block[0] > 0 ? 2 : 3);
i = 1;
} else {
i = 0;
}
/* AC coefs */
last_index = s->block_last_index[n];
last_non_zero = i - 1;
for (; i <= last_index; i++) {
j = s->intra_scantable.permutated[i];
level = block[j];
if (level) {
run = i - last_non_zero - 1;
sign = 0;
slevel = level;
if (level < 0) {
sign = 1;
level = -level;
}
code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/,
run, level);
if (run == 0 && level < 16)
code += 1;
put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
if (code == rl->n) {
put_bits(&s->pb, 6, run);
assert(slevel != 0);
assert(level <= 127);
put_sbits(&s->pb, 8, slevel);
} else {
put_bits(&s->pb, 1, sign);
}
last_non_zero = i;
}
}
if (last_index > -1)
put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]); // EOB
}
void ff_h261_encode_mb(MpegEncContext *s, int16_t block[6][64],
int motion_x, int motion_y)
{
@ -252,79 +322,6 @@ void ff_h261_encode_init(MpegEncContext *s)
s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
}
/**
* Encode an 8x8 block.
* @param block the 8x8 block
* @param n block index (0-3 are luma, 4-5 are chroma)
*/
static void h261_encode_block(H261Context *h, int16_t *block, int n)
{
MpegEncContext *const s = &h->s;
int level, run, i, j, last_index, last_non_zero, sign, slevel, code;
RLTable *rl;
rl = &h261_rl_tcoeff;
if (s->mb_intra) {
/* DC coef */
level = block[0];
/* 255 cannot be represented, so we clamp */
if (level > 254) {
level = 254;
block[0] = 254;
}
/* 0 cannot be represented also */
else if (level < 1) {
level = 1;
block[0] = 1;
}
if (level == 128)
put_bits(&s->pb, 8, 0xff);
else
put_bits(&s->pb, 8, level);
i = 1;
} else if ((block[0] == 1 || block[0] == -1) &&
(s->block_last_index[n] > -1)) {
// special case
put_bits(&s->pb, 2, block[0] > 0 ? 2 : 3);
i = 1;
} else {
i = 0;
}
/* AC coefs */
last_index = s->block_last_index[n];
last_non_zero = i - 1;
for (; i <= last_index; i++) {
j = s->intra_scantable.permutated[i];
level = block[j];
if (level) {
run = i - last_non_zero - 1;
sign = 0;
slevel = level;
if (level < 0) {
sign = 1;
level = -level;
}
code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/,
run, level);
if (run == 0 && level < 16)
code += 1;
put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
if (code == rl->n) {
put_bits(&s->pb, 6, run);
assert(slevel != 0);
assert(level <= 127);
put_sbits(&s->pb, 8, slevel);
} else {
put_bits(&s->pb, 1, sign);
}
last_non_zero = i;
}
}
if (last_index > -1)
put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]); // EOB
}
FF_MPV_GENERIC_CLASS(h261)
AVCodec ff_h261_encoder = {

Write Preview
Loading…
Cancel
Save