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authorDavid Conrad <lessen42@gmail.com>2010-03-03 23:27:43 +0000
committerDavid Conrad <lessen42@gmail.com>2010-03-03 23:27:43 +0000
commitc72625f29902bfd7f01184c3eb1c29c94ec2a648 (patch)
tree5b37448d3683813aa90e8d3a6e8a318dd6816fd2
parent7a095ea6fbf0bd26b02a783a0b2f2afd46f58578 (diff)
downloadffmpeg-c72625f29902bfd7f01184c3eb1c29c94ec2a648.tar.gz
Delay translating DCT tokens into coefficients until immediately before IDCT
This is generally around 12% faster than the prior method of creating a linked list for each block as tokens are read, but can be anywhere from 8% to 28% faster depending on file and CPU. Originally committed as revision 22190 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r--libavcodec/vp3.c355
1 files changed, 177 insertions, 178 deletions
diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c
index 46633a6821..e2ee24a54d 100644
--- a/libavcodec/vp3.c
+++ b/libavcodec/vp3.c
@@ -44,15 +44,9 @@
static av_cold int vp3_decode_end(AVCodecContext *avctx);
-typedef struct Coeff {
- struct Coeff *next;
- DCTELEM coeff;
- uint8_t index;
-} Coeff;
-
//FIXME split things out into their own arrays
typedef struct Vp3Fragment {
- Coeff *next_coeff;
+ int16_t dc;
uint8_t coding_method;
int8_t motion_x;
int8_t motion_y;
@@ -168,9 +162,6 @@ typedef struct Vp3DecodeContext {
int fragment_height;
Vp3Fragment *all_fragments;
- uint8_t *coeff_counts;
- Coeff *coeffs;
- Coeff *next_coeff;
int fragment_start[3];
int data_offset[3];
@@ -184,18 +175,38 @@ typedef struct Vp3DecodeContext {
uint8_t qr_size [2][3][64];
uint16_t qr_base[2][3][64];
+ /**
+ * This is a list of all tokens in bitstream order. Reordering takes place
+ * by pulling from each level during IDCT. As a consequence, IDCT must be
+ * in Hilbert order, making the minimum slice height 64 for 4:2:0 and 32
+ * otherwise. The 32 different tokens with up to 12 bits of extradata are
+ * collapsed into 3 types, packed as follows:
+ * (from the low to high bits)
+ *
+ * 2 bits: type (0,1,2)
+ * 0: EOB run, 14 bits for run length (12 needed)
+ * 1: zero run, 7 bits for run length
+ * 7 bits for the next coefficient (3 needed)
+ * 2: coefficient, 14 bits (11 needed)
+ *
+ * Coefficients are signed, so are packed in the highest bits for automatic
+ * sign extension.
+ */
+ int16_t *dct_tokens[3][64];
+ int16_t *dct_tokens_base;
+#define TOKEN_EOB(eob_run) ((eob_run) << 2)
+#define TOKEN_ZERO_RUN(coeff, zero_run) (((coeff) << 9) + ((zero_run) << 2) + 1)
+#define TOKEN_COEFF(coeff) (((coeff) << 2) + 2)
+
+ /**
+ * number of blocks that contain DCT coefficients at the given level or higher
+ */
+ int num_coded_frags[3][64];
+ int total_num_coded_frags;
+
/* this is a list of indexes into the all_fragments array indicating
* which of the fragments are coded */
- int *coded_fragment_list;
- int coded_fragment_list_index;
-
- /* track which fragments have already been decoded; called 'fast'
- * because this data structure avoids having to iterate through every
- * fragment in coded_fragment_list; once a fragment has been fully
- * decoded, it is removed from this list */
- int *fast_fragment_list;
- int fragment_list_y_head;
- int fragment_list_c_head;
+ int *coded_fragment_list[3];
VLC dc_vlc[16];
VLC ac_vlc_1[16];
@@ -222,11 +233,6 @@ typedef struct Vp3DecodeContext {
* is coded. */
unsigned char *macroblock_coding;
- int first_coded_y_fragment;
- int first_coded_c_fragment;
- int last_coded_y_fragment;
- int last_coded_c_fragment;
-
uint8_t edge_emu_buffer[9*2048]; //FIXME dynamic alloc
int8_t qscale_table[2048]; //FIXME dynamic alloc (width+15)/16
@@ -366,16 +372,11 @@ static void init_frame(Vp3DecodeContext *s, GetBitContext *gb)
int i;
/* zero out all of the fragment information */
- s->coded_fragment_list_index = 0;
for (i = 0; i < s->fragment_count; i++) {
- s->coeff_counts[i] = 0;
s->all_fragments[i].motion_x = 127;
s->all_fragments[i].motion_y = 127;
- s->all_fragments[i].next_coeff= NULL;
+ s->all_fragments[i].dc = 0;
s->all_fragments[i].qpi = 0;
- s->coeffs[i].index=
- s->coeffs[i].coeff=0;
- s->coeffs[i].next= NULL;
}
}
@@ -459,7 +460,6 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
int current_superblock = 0;
int current_run = 0;
int num_partial_superblocks = 0;
- int first_c_fragment_seen;
int i, j;
int current_fragment;
@@ -543,16 +543,13 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
/* figure out which fragments are coded; iterate through each
* superblock (all planes) */
- s->coded_fragment_list_index = 0;
- s->next_coeff= s->coeffs + s->fragment_count;
- s->first_coded_y_fragment = s->first_coded_c_fragment = 0;
- s->last_coded_y_fragment = s->last_coded_c_fragment = -1;
- first_c_fragment_seen = 0;
+ s->total_num_coded_frags = 0;
memset(s->macroblock_coding, MODE_COPY, s->macroblock_count);
for (plane = 0; plane < 3; plane++) {
int sb_start = (int[]){ 0, s->u_superblock_start, s->v_superblock_start }[plane];
int sb_end = sb_start + (plane ? s->c_superblock_count : s->y_superblock_count);
+ int num_coded_frags = 0;
for (i = sb_start; i < sb_end; i++) {
@@ -586,15 +583,8 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
* the next phase */
s->all_fragments[current_fragment].coding_method =
MODE_INTER_NO_MV;
- s->all_fragments[current_fragment].next_coeff= s->coeffs + current_fragment;
- s->coded_fragment_list[s->coded_fragment_list_index] =
+ s->coded_fragment_list[plane][num_coded_frags++] =
current_fragment;
- if (plane && !first_c_fragment_seen) {
- s->first_coded_c_fragment = s->coded_fragment_list_index;
- s->last_coded_y_fragment = s->first_coded_c_fragment - 1;
- first_c_fragment_seen = 1;
- }
- s->coded_fragment_list_index++;
} else {
/* not coded; copy this fragment from the prior frame */
s->all_fragments[current_fragment].coding_method =
@@ -603,34 +593,12 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb)
}
}
}
+ s->total_num_coded_frags += num_coded_frags;
+ for (i = 0; i < 64; i++)
+ s->num_coded_frags[plane][i] = num_coded_frags;
+ if (plane < 2)
+ s->coded_fragment_list[plane+1] = s->coded_fragment_list[plane] + num_coded_frags;
}
-
- if (!first_c_fragment_seen)
- /* only Y fragments coded in this frame */
- s->last_coded_y_fragment = s->coded_fragment_list_index - 1;
- else
- /* end the list of coded C fragments */
- s->last_coded_c_fragment = s->coded_fragment_list_index - 1;
-
- for (i = 0; i < s->fragment_count - 1; i++) {
- s->fast_fragment_list[i] = i + 1;
- }
- s->fast_fragment_list[s->fragment_count - 1] = -1;
-
- if (s->last_coded_y_fragment == -1)
- s->fragment_list_y_head = -1;
- else {
- s->fragment_list_y_head = s->first_coded_y_fragment;
- s->fast_fragment_list[s->last_coded_y_fragment] = -1;
- }
-
- if (s->last_coded_c_fragment == -1)
- s->fragment_list_c_head = -1;
- else {
- s->fragment_list_c_head = s->first_coded_c_fragment;
- s->fast_fragment_list[s->last_coded_c_fragment] = -1;
- }
-
return 0;
}
@@ -887,7 +855,7 @@ static int unpack_vectors(Vp3DecodeContext *s, GetBitContext *gb)
static int unpack_block_qpis(Vp3DecodeContext *s, GetBitContext *gb)
{
int qpi, i, j, bit, run_length, blocks_decoded, num_blocks_at_qpi;
- int num_blocks = s->coded_fragment_list_index;
+ int num_blocks = s->total_num_coded_frags;
for (qpi = 0; qpi < s->nqps-1 && num_blocks > 0; qpi++) {
i = blocks_decoded = num_blocks_at_qpi = 0;
@@ -904,11 +872,11 @@ static int unpack_block_qpis(Vp3DecodeContext *s, GetBitContext *gb)
num_blocks_at_qpi += run_length;
for (j = 0; j < run_length; i++) {
- if (i >= s->coded_fragment_list_index)
+ if (i >= s->total_num_coded_frags)
return -1;
- if (s->all_fragments[s->coded_fragment_list[i]].qpi == qpi) {
- s->all_fragments[s->coded_fragment_list[i]].qpi += bit;
+ if (s->all_fragments[s->coded_fragment_list[0][i]].qpi == qpi) {
+ s->all_fragments[s->coded_fragment_list[0][i]].qpi += bit;
j++;
}
}
@@ -939,49 +907,40 @@ static int unpack_block_qpis(Vp3DecodeContext *s, GetBitContext *gb)
*/
static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
VLC *table, int coeff_index,
- int y_plane,
+ int plane,
int eob_run)
{
- int i;
+ int i, j = 0;
int token;
int zero_run = 0;
DCTELEM coeff = 0;
- Vp3Fragment *fragment;
int bits_to_get;
- int next_fragment;
- int previous_fragment;
- int fragment_num;
- int *list_head;
+ int blocks_ended;
+ int coeff_i = 0;
+ int num_coeffs = s->num_coded_frags[plane][coeff_index];
+ int16_t *dct_tokens = s->dct_tokens[plane][coeff_index];
/* local references to structure members to avoid repeated deferences */
- uint8_t *perm= s->scantable.permutated;
- int *coded_fragment_list = s->coded_fragment_list;
+ int *coded_fragment_list = s->coded_fragment_list[plane];
Vp3Fragment *all_fragments = s->all_fragments;
- uint8_t *coeff_counts = s->coeff_counts;
VLC_TYPE (*vlc_table)[2] = table->table;
- int *fast_fragment_list = s->fast_fragment_list;
- if (y_plane) {
- next_fragment = s->fragment_list_y_head;
- list_head = &s->fragment_list_y_head;
+ if (num_coeffs < 0)
+ av_log(s->avctx, AV_LOG_ERROR, "Invalid number of coefficents at level %d\n", coeff_index);
+
+ if (eob_run > num_coeffs) {
+ coeff_i = blocks_ended = num_coeffs;
+ eob_run -= num_coeffs;
} else {
- next_fragment = s->fragment_list_c_head;
- list_head = &s->fragment_list_c_head;
+ coeff_i = blocks_ended = eob_run;
+ eob_run = 0;
}
- i = next_fragment;
- previous_fragment = -1; /* this indicates that the previous fragment is actually the list head */
- while (i != -1) {
- fragment_num = coded_fragment_list[i];
+ // insert fake EOB token to cover the split between planes or zzi
+ if (blocks_ended)
+ dct_tokens[j++] = blocks_ended << 2;
- if (coeff_counts[fragment_num] > coeff_index) {
- previous_fragment = i;
- i = fast_fragment_list[i];
- continue;
- }
- fragment = &all_fragments[fragment_num];
-
- if (!eob_run) {
+ while (coeff_i < num_coeffs) {
/* decode a VLC into a token */
token = get_vlc2(gb, vlc_table, 5, 3);
/* use the token to get a zero run, a coefficient, and an eob run */
@@ -989,7 +948,20 @@ static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
eob_run = eob_run_base[token];
if (eob_run_get_bits[token])
eob_run += get_bits(gb, eob_run_get_bits[token]);
- coeff = zero_run = 0;
+
+ // record only the number of blocks ended in this plane,
+ // any spill will be recorded in the next plane.
+ if (eob_run > num_coeffs - coeff_i) {
+ dct_tokens[j++] = TOKEN_EOB(num_coeffs - coeff_i);
+ blocks_ended += num_coeffs - coeff_i;
+ eob_run -= num_coeffs - coeff_i;
+ coeff_i = num_coeffs;
+ } else {
+ dct_tokens[j++] = TOKEN_EOB(eob_run);
+ blocks_ended += eob_run;
+ coeff_i += eob_run;
+ eob_run = 0;
+ }
} else {
bits_to_get = coeff_get_bits[token];
if (bits_to_get)
@@ -999,34 +971,49 @@ static int unpack_vlcs(Vp3DecodeContext *s, GetBitContext *gb,
zero_run = zero_run_base[token];
if (zero_run_get_bits[token])
zero_run += get_bits(gb, zero_run_get_bits[token]);
- }
- }
- if (!eob_run) {
- coeff_counts[fragment_num] += zero_run;
- if (coeff_counts[fragment_num] < 64){
- fragment->next_coeff->coeff= coeff;
- fragment->next_coeff->index= perm[coeff_counts[fragment_num]++]; //FIXME perm here already?
- fragment->next_coeff->next= s->next_coeff;
- s->next_coeff->next=NULL;
- fragment->next_coeff= s->next_coeff++;
- }
- /* previous fragment is now this fragment */
- previous_fragment = i;
- } else {
- coeff_counts[fragment_num] |= 128;
- eob_run--;
- /* remove this fragment from the list */
- if (previous_fragment != -1)
- fast_fragment_list[previous_fragment] = fast_fragment_list[i];
- else
- *list_head = fast_fragment_list[i];
- /* previous fragment remains unchanged */
- }
+ if (zero_run) {
+ dct_tokens[j++] = TOKEN_ZERO_RUN(coeff, zero_run);
+ } else {
+ // Save DC into the fragment structure. DC prediction is
+ // done in raster order, so the actual DC can't be in with
+ // other tokens. We still need the token in dct_tokens[]
+ // however, or else the structure collapses on itself.
+ if (!coeff_index)
+ all_fragments[coded_fragment_list[coeff_i]].dc = coeff;
+
+ dct_tokens[j++] = TOKEN_COEFF(coeff);
+ }
+
+ if (coeff_index + zero_run > 64) {
+ av_log(s->avctx, AV_LOG_ERROR, "Invalid zero run of %d with"
+ " %d coeffs left\n", zero_run, 64-coeff_index);
+ zero_run = 64 - coeff_index;
+ }
- i = fast_fragment_list[i];
+ // zero runs code multiple coefficients,
+ // so don't try to decode coeffs for those higher levels
+ for (i = coeff_index+1; i <= coeff_index+zero_run; i++)
+ s->num_coded_frags[plane][i]--;
+ coeff_i++;
+ }
}
+ if (blocks_ended > s->num_coded_frags[plane][coeff_index])
+ av_log(s->avctx, AV_LOG_ERROR, "More blocks ended than coded!\n");
+
+ // decrement the number of blocks that have higher coeffecients for each
+ // EOB run at this level
+ if (blocks_ended)
+ for (i = coeff_index+1; i < 64; i++)
+ s->num_coded_frags[plane][i] -= blocks_ended;
+
+ // setup the next buffer
+ if (plane < 2)
+ s->dct_tokens[plane+1][coeff_index] = dct_tokens + j;
+ else if (coeff_index < 63)
+ s->dct_tokens[0][coeff_index+1] = dct_tokens + j;
+
return eob_run;
}
@@ -1049,20 +1036,24 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
VLC *y_tables[64];
VLC *c_tables[64];
+ s->dct_tokens[0][0] = s->dct_tokens_base;
+
/* fetch the DC table indexes */
dc_y_table = get_bits(gb, 4);
dc_c_table = get_bits(gb, 4);
/* unpack the Y plane DC coefficients */
residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_y_table], 0,
- 1, residual_eob_run);
+ 0, residual_eob_run);
/* reverse prediction of the Y-plane DC coefficients */
reverse_dc_prediction(s, 0, s->fragment_width, s->fragment_height);
/* unpack the C plane DC coefficients */
residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_c_table], 0,
- 0, residual_eob_run);
+ 1, residual_eob_run);
+ residual_eob_run = unpack_vlcs(s, gb, &s->dc_vlc[dc_c_table], 0,
+ 2, residual_eob_run);
/* reverse prediction of the C-plane DC coefficients */
if (!(s->avctx->flags & CODEC_FLAG_GRAY))
@@ -1097,13 +1088,13 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
/* decode all AC coefficents */
for (i = 1; i <= 63; i++) {
- if (s->fragment_list_y_head != -1)
residual_eob_run = unpack_vlcs(s, gb, y_tables[i], i,
- 1, residual_eob_run);
+ 0, residual_eob_run);
- if (s->fragment_list_c_head != -1)
residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i,
- 0, residual_eob_run);
+ 1, residual_eob_run);
+ residual_eob_run = unpack_vlcs(s, gb, c_tables[i], i,
+ 2, residual_eob_run);
}
return 0;
@@ -1116,7 +1107,7 @@ static int unpack_dct_coeffs(Vp3DecodeContext *s, GetBitContext *gb)
*/
#define COMPATIBLE_FRAME(x) \
(compatible_frame[s->all_fragments[x].coding_method] == current_frame_type)
-#define DC_COEFF(u) (s->coeffs[u].index ? 0 : s->coeffs[u].coeff) //FIXME do somethin to simplify this
+#define DC_COEFF(u) s->all_fragments[u].dc
static void reverse_dc_prediction(Vp3DecodeContext *s,
int first_fragment,
@@ -1260,21 +1251,9 @@ static void reverse_dc_prediction(Vp3DecodeContext *s,
}
/* at long last, apply the predictor */
- if(s->coeffs[i].index){
- *s->next_coeff= s->coeffs[i];
- s->coeffs[i].index=0;
- s->coeffs[i].coeff=0;
- s->coeffs[i].next= s->next_coeff++;
- }
- s->coeffs[i].coeff += predicted_dc;
+ DC_COEFF(i) += predicted_dc;
/* save the DC */
last_dc[current_frame_type] = DC_COEFF(i);
- if(DC_COEFF(i) && !(s->coeff_counts[i]&127)){
- s->coeff_counts[i]= 129;
-// s->all_fragments[i].next_coeff= s->next_coeff;
- s->coeffs[i].next= s->next_coeff;
- (s->next_coeff++)->next=NULL;
- }
}
}
}
@@ -1344,6 +1323,47 @@ static void apply_loop_filter(Vp3DecodeContext *s, int plane, int ystart, int ye
}
/**
+ * Pulls DCT tokens from the 64 levels to decode and dequant the coefficients
+ * for the next block in coding order
+ */
+static inline int vp3_dequant(Vp3DecodeContext *s, Vp3Fragment *frag,
+ int plane, int inter, DCTELEM block[64])
+{
+ int16_t *dequantizer = s->qmat[frag->qpi][inter][plane];
+ uint8_t *perm = s->scantable.permutated;
+ int i = 0;
+
+ do {
+ int token = *s->dct_tokens[plane][i];
+ switch (token & 3) {
+ case 0: // EOB
+ if (--token < 4) // 0-3 are token types, so the EOB run must now be 0
+ s->dct_tokens[plane][i]++;
+ else
+ *s->dct_tokens[plane][i] = token & ~3;
+ goto end;
+ case 1: // zero run
+ s->dct_tokens[plane][i]++;
+ i += (token >> 2) & 0x7f;
+ block[perm[i]] = (token >> 9) * dequantizer[perm[i]];
+ i++;
+ break;
+ case 2: // coeff
+ block[perm[i]] = (token >> 2) * dequantizer[perm[i]];
+ s->dct_tokens[plane][i++]++;
+ break;
+ default:
+ av_log(s->avctx, AV_LOG_ERROR, "internal: invalid token type\n");
+ return i;
+ }
+ } while (i < 64);
+end:
+ // the actual DC+prediction is in the fragment structure
+ block[0] = frag->dc * s->qmat[0][inter][plane][0];
+ return i;
+}
+
+/**
* called when all pixels up to row y are complete
*/
static void vp3_draw_horiz_band(Vp3DecodeContext *s, int y)
@@ -1381,7 +1401,6 @@ static void vp3_draw_horiz_band(Vp3DecodeContext *s, int y)
static void render_slice(Vp3DecodeContext *s, int slice)
{
int x, y, i, j;
- int16_t *dequantizer;
LOCAL_ALIGNED_16(DCTELEM, block, [64]);
int motion_x = 0xdeadbeef, motion_y = 0xdeadbeef;
int motion_halfpel_index;
@@ -1436,6 +1455,7 @@ static void render_slice(Vp3DecodeContext *s, int slice)
/* transform if this block was coded */
if (s->all_fragments[i].coding_method != MODE_COPY) {
+ int intra = s->all_fragments[i].coding_method == MODE_INTRA;
if ((s->all_fragments[i].coding_method == MODE_USING_GOLDEN) ||
(s->all_fragments[i].coding_method == MODE_GOLDEN_MV))
@@ -1499,27 +1519,10 @@ static void render_slice(Vp3DecodeContext *s, int slice)
motion_source + stride + 1 + d,
stride, 8);
}
- dequantizer = s->qmat[s->all_fragments[i].qpi][1][plane];
- }else{
- dequantizer = s->qmat[s->all_fragments[i].qpi][0][plane];
}
- /* dequantize the DCT coefficients */
- if(s->avctx->idct_algo==FF_IDCT_VP3){
- Coeff *coeff= s->coeffs + i;
s->dsp.clear_block(block);
- while(coeff->next){
- block[coeff->index]= coeff->coeff * dequantizer[coeff->index];
- coeff= coeff->next;
- }
- }else{
- Coeff *coeff= s->coeffs + i;
- s->dsp.clear_block(block);
- while(coeff->next){
- block[coeff->index]= (coeff->coeff * dequantizer[coeff->index] + 2)>>2;
- coeff= coeff->next;
- }
- }
+ vp3_dequant(s, s->all_fragments + i, plane, !intra, block);
/* invert DCT and place (or add) in final output */
@@ -1624,12 +1627,10 @@ static av_cold int vp3_decode_init(AVCodecContext *avctx)
s->fragment_start[2] = s->fragment_width * s->fragment_height * 5 / 4;
s->all_fragments = av_malloc(s->fragment_count * sizeof(Vp3Fragment));
- s->coeff_counts = av_malloc(s->fragment_count * sizeof(*s->coeff_counts));
- s->coeffs = av_malloc(s->fragment_count * sizeof(Coeff) * 65);
- s->coded_fragment_list = av_malloc(s->fragment_count * sizeof(int));
- s->fast_fragment_list = av_malloc(s->fragment_count * sizeof(int));
- if (!s->superblock_coding || !s->all_fragments || !s->coeff_counts ||
- !s->coeffs || !s->coded_fragment_list || !s->fast_fragment_list) {
+ s->coded_fragment_list[0] = av_malloc(s->fragment_count * sizeof(int));
+ s->dct_tokens_base = av_malloc(64*s->fragment_count * sizeof(*s->dct_tokens_base));
+ if (!s->superblock_coding || !s->all_fragments || !s->dct_tokens_base ||
+ !s->coded_fragment_list[0]) {
vp3_decode_end(avctx);
return -1;
}
@@ -1928,10 +1929,8 @@ static av_cold int vp3_decode_end(AVCodecContext *avctx)
av_free(s->superblock_coding);
av_free(s->all_fragments);
- av_free(s->coeff_counts);
- av_free(s->coeffs);
- av_free(s->coded_fragment_list);
- av_free(s->fast_fragment_list);
+ av_free(s->coded_fragment_list[0]);
+ av_free(s->dct_tokens_base);
av_free(s->superblock_fragments);
av_free(s->macroblock_coding);