/*
- * H261 decoder
+ * H.261 decoder
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
* Copyright (c) 2004 Maarten Daniels
*
*/
#include "avcodec.h"
+#include "bitstream.h"
+#include "mpeg_er.h"
+#include "mpegutils.h"
#include "mpegvideo.h"
#include "h263.h"
#include "h261.h"
-#include "h261data.h"
+#include "internal.h"
+#include "vlc.h"
#define H261_MBA_VLC_BITS 9
#define H261_MTYPE_VLC_BITS 6
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;
if (!done) {
done = 1;
INIT_VLC_STATIC(&h261_mba_vlc, H261_MBA_VLC_BITS, 35,
- h261_mba_bits, 1, 1,
- h261_mba_code, 1, 1, 662);
+ ff_h261_mba_bits, 1, 1,
+ ff_h261_mba_code, 1, 1, 662);
INIT_VLC_STATIC(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10,
- h261_mtype_bits, 1, 1,
- h261_mtype_code, 1, 1, 80);
+ ff_h261_mtype_bits, 1, 1,
+ ff_h261_mtype_code, 1, 1, 80);
INIT_VLC_STATIC(&h261_mv_vlc, H261_MV_VLC_BITS, 17,
- &h261_mv_tab[0][1], 2, 1,
- &h261_mv_tab[0][0], 2, 1, 144);
+ &ff_h261_mv_tab[0][1], 2, 1,
+ &ff_h261_mv_tab[0][0], 2, 1, 144);
INIT_VLC_STATIC(&h261_cbp_vlc, H261_CBP_VLC_BITS, 63,
- &h261_cbp_tab[0][1], 2, 1,
- &h261_cbp_tab[0][0], 2, 1, 512);
- ff_init_rl(&h261_rl_tcoeff, ff_h261_rl_table_store);
- INIT_VLC_RL(h261_rl_tcoeff, 552);
+ &ff_h261_cbp_tab[0][1], 2, 1,
+ &ff_h261_cbp_tab[0][0], 2, 1, 512);
+ INIT_VLC_RL(ff_h261_rl_tcoeff, 552);
}
}
MpegEncContext *const s = &h->s;
// set defaults
- ff_MPV_decode_defaults(s);
+ ff_mpv_decode_defaults(s);
s->avctx = avctx;
s->width = s->avctx->coded_width;
s->height = s->avctx->coded_height;
avctx->pix_fmt = AV_PIX_FMT_YUV420P;
s->codec_id = avctx->codec->id;
+ ff_h261_common_init();
h261_decode_init_vlc(h);
h->gob_start_code_skipped = 0;
if (!h->gob_start_code_skipped) {
/* Check for GOB Start Code */
- val = show_bits(&s->gb, 15);
+ val = bitstream_peek(&s->bc, 15);
if (val)
return -1;
/* We have a GBSC */
- skip_bits(&s->gb, 16);
+ bitstream_skip(&s->bc, 16);
}
h->gob_start_code_skipped = 0;
- h->gob_number = get_bits(&s->gb, 4); /* GN */
- s->qscale = get_bits(&s->gb, 5); /* GQUANT */
+ h->gob_number = bitstream_read(&s->bc, 4); /* GN */
+ s->qscale = bitstream_read(&s->bc, 5); /* GQUANT */
/* Check if gob_number is valid */
if (s->mb_height == 18) { // CIF
}
/* GEI */
- while (get_bits1(&s->gb) != 0)
- skip_bits(&s->gb, 8);
+ while (bitstream_read_bit(&s->bc) != 0)
+ bitstream_skip(&s->bc, 8);
if (s->qscale == 0) {
av_log(s->avctx, AV_LOG_ERROR, "qscale has forbidden 0 value\n");
* Decode the group of blocks / video packet header.
* @return <0 if no resync found
*/
-static int ff_h261_resync(H261Context *h)
+static int h261_resync(H261Context *h)
{
MpegEncContext *const s = &h->s;
int left, ret;
if (ret >= 0)
return 0;
} else {
- if (show_bits(&s->gb, 15) == 0) {
+ if (bitstream_peek(&s->bc, 15) == 0) {
ret = h261_decode_gob_header(h);
if (ret >= 0)
return 0;
}
// OK, it is not where it is supposed to be ...
- s->gb = s->last_resync_gb;
- align_get_bits(&s->gb);
- left = get_bits_left(&s->gb);
+ s->bc = s->last_resync_bc;
+ bitstream_align(&s->bc);
+ left = bitstream_bits_left(&s->bc);
for (; left > 15 + 1 + 4 + 5; left -= 8) {
- if (show_bits(&s->gb, 15) == 0) {
- GetBitContext bak = s->gb;
+ if (bitstream_peek(&s->bc, 15) == 0) {
+ BitstreamContext bak = s->bc;
ret = h261_decode_gob_header(h);
if (ret >= 0)
return 0;
- s->gb = bak;
+ s->bc = bak;
}
- skip_bits(&s->gb, 8);
+ bitstream_skip(&s->bc, 8);
}
}
s->mb_skipped = 1;
h->mtype &= ~MB_TYPE_H261_FIL;
- ff_MPV_decode_mb(s, s->block);
+ ff_mpv_decode_mb(s, s->block);
}
return 0;
}
-static int decode_mv_component(GetBitContext *gb, int v)
+static const int mvmap[17] = {
+ 0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15, -16
+};
+
+static int decode_mv_component(BitstreamContext *bc, int v)
{
- int mv_diff = get_vlc2(gb, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
+ int mv_diff = bitstream_read_vlc(bc, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
/* check if mv_diff is valid */
if (mv_diff < 0)
mv_diff = mvmap[mv_diff];
- if (mv_diff && !get_bits1(gb))
+ if (mv_diff && !bitstream_read_bit(bc))
mv_diff = -mv_diff;
v += mv_diff;
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 = &ff_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 = bitstream_read(&s->bc, 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 = bitstream_peek(&s->bc, 2);
+ i = 0;
+ if (check & 0x2) {
+ bitstream_skip(&s->bc, 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 = bitstream_read_vlc(&s->bc, 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 = bitstream_read(&s->bc, 6);
+ level = bitstream_read_signed(&s->bc, 8);
+ } else if (code == 0) {
+ break;
+ } else {
+ run = rl->table_run[code];
+ level = rl->table_level[code];
+ if (bitstream_read_bit(&s->bc))
+ 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;
cbp = 63;
// Read mba
do {
- h->mba_diff = get_vlc2(&s->gb, h261_mba_vlc.table,
- H261_MBA_VLC_BITS, 2);
+ h->mba_diff = bitstream_read_vlc(&s->bc, h261_mba_vlc.table,
+ H261_MBA_VLC_BITS, 2);
/* Check for slice end */
/* NOTE: GOB can be empty (no MB data) or exist only of MBA_stuffing */
} while (h->mba_diff == MBA_STUFFING); // stuffing
if (h->mba_diff < 0) {
- if (get_bits_left(&s->gb) <= 7)
+ if (bitstream_bits_left(&s->bc) <= 7)
return SLICE_END;
av_log(s->avctx, AV_LOG_ERROR, "illegal mba at %d %d\n", s->mb_x, s->mb_y);
ff_update_block_index(s);
// Read mtype
- h->mtype = get_vlc2(&s->gb, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
- h->mtype = h261_mtype_map[h->mtype];
+ h->mtype = bitstream_read_vlc(&s->bc, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
+ if (h->mtype < 0 || h->mtype >= FF_ARRAY_ELEMS(ff_h261_mtype_map)) {
+ av_log(s->avctx, AV_LOG_ERROR, "Invalid mtype index %d\n",
+ h->mtype);
+ return SLICE_ERROR;
+ }
+ h->mtype = ff_h261_mtype_map[h->mtype];
// Read mquant
if (IS_QUANT(h->mtype))
- ff_set_qscale(s, get_bits(&s->gb, 5));
+ ff_set_qscale(s, bitstream_read(&s->bc, 5));
s->mb_intra = IS_INTRA4x4(h->mtype);
h->current_mv_y = 0;
}
- h->current_mv_x = decode_mv_component(&s->gb, h->current_mv_x);
- h->current_mv_y = decode_mv_component(&s->gb, h->current_mv_y);
+ h->current_mv_x = decode_mv_component(&s->bc, h->current_mv_x);
+ h->current_mv_y = decode_mv_component(&s->bc, h->current_mv_y);
} else {
h->current_mv_x = 0;
h->current_mv_y = 0;
// Read cbp
if (HAS_CBP(h->mtype))
- cbp = get_vlc2(&s->gb, h261_cbp_vlc.table, H261_CBP_VLC_BITS, 2) + 1;
+ cbp = bitstream_read_vlc(&s->bc, h261_cbp_vlc.table, H261_CBP_VLC_BITS, 2) + 1;
if (s->mb_intra) {
s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
intra:
/* decode each block */
if (s->mb_intra || HAS_CBP(h->mtype)) {
- s->dsp.clear_blocks(s->block[0]);
+ s->bdsp.clear_blocks(s->block[0]);
for (i = 0; i < 6; i++) {
if (h261_decode_block(h, s->block[i], i, cbp & 32) < 0)
return SLICE_ERROR;
s->block_last_index[i] = -1;
}
- ff_MPV_decode_mb(s, s->block);
+ ff_mpv_decode_mb(s, s->block);
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
int format, i;
uint32_t startcode = 0;
- for (i = get_bits_left(&s->gb); i > 24; i -= 1) {
- startcode = ((startcode << 1) | get_bits(&s->gb, 1)) & 0x000FFFFF;
+ for (i = bitstream_bits_left(&s->bc); i > 24; i -= 1) {
+ startcode = ((startcode << 1) | bitstream_read(&s->bc, 1)) & 0x000FFFFF;
if (startcode == 0x10)
break;
}
/* temporal reference */
- i = get_bits(&s->gb, 5); /* picture timestamp */
+ i = bitstream_read(&s->bc, 5); /* picture timestamp */
if (i < (s->picture_number & 31))
i += 32;
s->picture_number = (s->picture_number & ~31) + i;
- s->avctx->time_base = (AVRational) { 1001, 30000 };
- s->current_picture.f.pts = s->picture_number;
+ s->avctx->framerate = (AVRational) { 30000, 1001 };
/* PTYPE starts here */
- skip_bits1(&s->gb); /* split screen off */
- skip_bits1(&s->gb); /* camera off */
- skip_bits1(&s->gb); /* freeze picture release off */
+ bitstream_skip(&s->bc, 1); /* split screen off */
+ bitstream_skip(&s->bc, 1); /* camera off */
+ bitstream_skip(&s->bc, 1); /* freeze picture release off */
- format = get_bits1(&s->gb);
+ format = bitstream_read_bit(&s->bc);
// only 2 formats possible
if (format == 0) { // QCIF
s->mb_num = s->mb_width * s->mb_height;
- skip_bits1(&s->gb); /* still image mode off */
- skip_bits1(&s->gb); /* Reserved */
+ bitstream_skip(&s->bc, 1); /* still image mode off */
+ bitstream_skip(&s->bc, 1); /* Reserved */
/* PEI */
- while (get_bits1(&s->gb) != 0)
- skip_bits(&s->gb, 8);
+ while (bitstream_read_bit(&s->bc) != 0)
+ bitstream_skip(&s->bc, 8);
/* H.261 has no I-frames, but if we pass AV_PICTURE_TYPE_I for the first
* frame, the codec crashes if it does not contain all I-blocks
*/
static int get_consumed_bytes(MpegEncContext *s, int buf_size)
{
- int pos = get_bits_count(&s->gb) >> 3;
+ int pos = bitstream_tell(&s->bc) >> 3;
if (pos == 0)
pos = 1; // avoid infinite loops (i doubt that is needed but ...)
if (pos + 10 > buf_size)
int ret;
AVFrame *pict = data;
- av_dlog(avctx, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
- av_dlog(avctx, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
- s->flags = avctx->flags;
- s->flags2 = avctx->flags2;
+ ff_dlog(avctx, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
+ ff_dlog(avctx, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
h->gob_start_code_skipped = 0;
retry:
- init_get_bits(&s->gb, buf, buf_size * 8);
+ bitstream_init8(&s->bc, buf, buf_size);
if (!s->context_initialized)
- // we need the IDCT permutaton for reading a custom matrix
- if (ff_MPV_common_init(s) < 0)
- return -1;
-
- /* We need to set current_picture_ptr before reading the header,
- * otherwise we cannot store anything in there. */
- if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
- int i = ff_find_unused_picture(s, 0);
- if (i < 0)
- return i;
- s->current_picture_ptr = &s->picture[i];
- }
+ // we need the IDCT permutation for reading a custom matrix
+ ff_mpv_idct_init(s);
ret = h261_decode_picture_header(h);
if (s->width != avctx->coded_width || s->height != avctx->coded_height) {
ParseContext pc = s->parse_context; // FIXME move this demuxing hack to libavformat
s->parse_context.buffer = 0;
- ff_MPV_common_end(s);
+ ff_mpv_common_end(s);
s->parse_context = pc;
}
+
if (!s->context_initialized) {
- avcodec_set_dimensions(avctx, s->width, s->height);
+ if ((ret = ff_mpv_common_init(s)) < 0)
+ return ret;
+
+ ret = ff_set_dimensions(avctx, s->width, s->height);
+ if (ret < 0)
+ return ret;
goto retry;
}
// for skipping the frame
- s->current_picture.f.pict_type = s->pict_type;
- s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
+ s->current_picture.f->pict_type = s->pict_type;
+ s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
if ((avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type == AV_PICTURE_TYPE_B) ||
(avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type != AV_PICTURE_TYPE_I) ||
avctx->skip_frame >= AVDISCARD_ALL)
return get_consumed_bytes(s, buf_size);
- if (ff_MPV_frame_start(s, avctx) < 0)
+ if (ff_mpv_frame_start(s, avctx) < 0)
return -1;
ff_mpeg_er_frame_start(s);
s->mb_y = 0;
while (h->gob_number < (s->mb_height == 18 ? 12 : 5)) {
- if (ff_h261_resync(h) < 0)
+ if (h261_resync(h) < 0)
break;
h261_decode_gob(h);
}
- ff_MPV_frame_end(s);
+ ff_mpv_frame_end(s);
- assert(s->current_picture.f.pict_type == s->current_picture_ptr->f.pict_type);
- assert(s->current_picture.f.pict_type == s->pict_type);
+ assert(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type);
+ assert(s->current_picture.f->pict_type == s->pict_type);
- if ((ret = av_frame_ref(pict, &s->current_picture_ptr->f)) < 0)
+ if ((ret = av_frame_ref(pict, s->current_picture_ptr->f)) < 0)
return ret;
ff_print_debug_info(s, s->current_picture_ptr);
H261Context *h = avctx->priv_data;
MpegEncContext *s = &h->s;
- ff_MPV_common_end(s);
+ ff_mpv_common_end(s);
return 0;
}
AVCodec ff_h261_decoder = {
.name = "h261",
+ .long_name = NULL_IF_CONFIG_SMALL("H.261"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_H261,
.priv_data_size = sizeof(H261Context),
.init = h261_decode_init,
.close = h261_decode_end,
.decode = h261_decode_frame,
- .capabilities = CODEC_CAP_DR1,
- .long_name = NULL_IF_CONFIG_SMALL("H.261"),
+ .capabilities = AV_CODEC_CAP_DR1,
};
projects / ffmpeg / blobdiff