first working version of DV video decoder

Originally committed as revision 998 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 632 insertions, 0 deletions

diff --git a/libavcodec/dv.c b/libavcodec/dv.c
new file mode 100644
index 0000000000..0077474c6a
--- /dev/null
+++ b/libavcodec/dv.c
@@ -0,0 +1,632 @@
+/*
+ * DV decoder
+ * Copyright (c) 2002 Fabrice Bellard.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "avcodec.h"
+#include "dsputil.h"
+#include "mpegvideo.h"
+#include "simple_idct.h"
+
+#define NTSC_FRAME_SIZE 120000
+#define PAL_FRAME_SIZE  144000
+
+#define TEX_VLC_BITS 9
+
+typedef struct DVVideoDecodeContext {
+    AVCodecContext *avctx;
+    GetBitContext gb;
+    VLC *vlc;
+    int sampling_411; /* 0 = 420, 1 = 411 */
+    int width, height;
+    UINT8 *current_picture[3]; /* picture structure */
+    int linesize[3];
+    DCTELEM block[5*6][64] __align8;
+    UINT8 dv_zigzag[2][64];
+    /* XXX: move it to static storage ? */
+    UINT8 dv_shift[2][2][22][64];
+    void (*idct_put[2])(UINT8 *dest, int line_size, DCTELEM *block);
+} DVVideoDecodeContext;
+
+#include "dvdata.h"
+
+static VLC dv_vlc;
+/* XXX: also include quantization */
+static RL_VLC_ELEM *dv_rl_vlc[1];
+
+static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
+{
+    int i, e, q;
+
+    /* NOTE: max left shift is 6 */
+    for(e = 0; e < 2; e++) {
+        for(q = 0; q < 22; q++) {
+            /* 88 unquant */
+            for(i = 1; i < 64; i++) {
+                /* 88 table */
+                s->dv_shift[0][e][q][i] =  
+                    dv_quant_shifts[q][dv_88_areas[i]] + e + 1;
+            }
+
+            /* 248 unquant */
+            for(i = 1; i < 64; i++) {
+                /* 248 table */
+                s->dv_shift[1][e][q][i] =  
+                    dv_quant_shifts[q][dv_248_areas[i]] + e + 1;
+            }
+        }
+    }
+}
+
+static int dvvideo_decode_init(AVCodecContext *avctx)
+{
+    DVVideoDecodeContext *s = avctx->priv_data;
+    static int done;
+
+    if (!done) {
+        int i;
+
+        done = 1;
+
+        /* NOTE: as a trick, we use the fact the no codes are unused
+           to accelerate the parsing of partial codes */
+        init_vlc(&dv_vlc, TEX_VLC_BITS, NB_DV_VLC, 
+                 dv_vlc_len, 1, 1, dv_vlc_bits, 2, 2);
+
+        dv_rl_vlc[0] = av_malloc(dv_vlc.table_size * sizeof(RL_VLC_ELEM));
+        for(i = 0; i < dv_vlc.table_size; i++){
+            int code= dv_vlc.table[i][0];
+            int len = dv_vlc.table[i][1];
+            int level, run;
+        
+            if(len<0){ //more bits needed
+                run= 0;
+                level= code;
+            } else if (code == (NB_DV_VLC - 1)) {
+                /* EOB */
+                run = 0;
+                level = 256;
+            } else {
+                run=   dv_vlc_run[code] + 1;
+                level= dv_vlc_level[code];
+            }
+            dv_rl_vlc[0][i].len = len;
+            dv_rl_vlc[0][i].level = level;
+            dv_rl_vlc[0][i].run = run;
+        }
+    }
+    /* XXX: do it only for constant case */
+    dv_build_unquantize_tables(s);
+    {
+        /* XXX: fix that : use mmx when possible */
+        s->idct_put[0] = simple_idct_put;
+        s->idct_put[1] = simple_idct248_put;
+
+        memcpy(s->dv_zigzag[0], ff_zigzag_direct, 64);
+        memcpy(s->dv_zigzag[1], dv_248_zigzag, 64);
+    }
+    return 0;
+}
+
+//#define VLC_DEBUG
+
+typedef struct MBInfo {
+    const UINT8 *shift_table[6];
+    const UINT8 *scan_table[6];
+    UINT8 pos[6]; /* position in block */
+    UINT8 eob_reached[6]; /* true if EOB has been reached */
+    UINT8 dct_mode[6];
+    UINT8 partial_bit_count[6];
+    UINT16 partial_bit_buffer[6];
+    UINT8 bit_buffer[80 + 4]; /* allow some slack */
+    int bits_left;
+} MBInfo;
+
+/* block size in bits */
+const static UINT16 block_sizes[6] = {
+    112, 112, 112, 112, 80, 80
+};
+
+#ifndef ALT_BITSTREAM_READER
+#error only works with ALT_BITSTREAM_READER
+#endif
+
+/* decode ac coefs */
+static void dv_decode_ac(DVVideoDecodeContext *s, 
+                         MBInfo *mb, INT16 *block, int j, int last_index)
+{
+    int last_re_index;
+    const UINT8 *scan_table = mb->scan_table[j];
+    const UINT8 *shift_table = mb->shift_table[j];
+    int pos = mb->pos[j];
+    int level, pos1, sign, run;
+    int partial_bit_count;
+
+    OPEN_READER(re, &s->gb);
+    
+#ifdef VLC_DEBUG
+    printf("start %d\n", j);
+#endif
+
+    /* if we must parse a partial vlc, we do it here */
+    partial_bit_count = mb->partial_bit_count[j];
+    if (partial_bit_count > 0) {
+        UINT8 buf[4];
+        UINT32 v;
+        int l, l1;
+        GetBitContext gb1;
+
+        /* build the dummy bit buffer */
+        l = 16 - partial_bit_count;
+        UPDATE_CACHE(re, &s->gb);
+#ifdef VLC_DEBUG
+        printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16));
+#endif
+        v = (mb->partial_bit_buffer[j] << l) | SHOW_UBITS(re, &s->gb, l);
+        buf[0] = v >> 8;
+        buf[1] = v;
+#ifdef VLC_DEBUG
+        printf("v=%04x cnt=%d %04x\n", 
+               v, partial_bit_count, (mb->partial_bit_buffer[j] << l));
+#endif
+        /* try to read the codeword */
+        init_get_bits(&gb1, buf, 4);
+        {
+            OPEN_READER(re1, &gb1);
+            UPDATE_CACHE(re1, &gb1);
+            GET_RL_VLC(level, run, re1, &gb1, dv_rl_vlc[0], 
+                       TEX_VLC_BITS, 2);
+            l = re1_index;
+            CLOSE_READER(re1, &gb1);
+        }
+#ifdef VLC_DEBUG
+        printf("****run=%d level=%d size=%d\n", run, level, l);
+#endif
+        /* compute codeword length */
+        l1 = (level != 256 && level != 0);
+        /* if too long, we cannot parse */
+        l -= partial_bit_count;
+        if ((re_index + l + l1) > last_index)
+            return;
+        /* skip read bits */
+        last_re_index = 0; /* avoid warning */
+        re_index += l;
+        /* by redefinition, if we can read the vlc, all partial bits
+           will be read (otherwise we could have read the vlc before) */
+        mb->partial_bit_count[j] = 0;
+        UPDATE_CACHE(re, &s->gb);
+        goto handle_vlc;
+    }
+
+    /* get the AC coefficients until last_index is reached */
+    for(;;) {
+        UPDATE_CACHE(re, &s->gb);
+#ifdef VLC_DEBUG
+        printf("%2d: bits=%04x index=%d\n", 
+               pos, SHOW_UBITS(re, &s->gb, 16), re_index);
+#endif
+        last_re_index = re_index;
+        GET_RL_VLC(level, run, re, &s->gb, dv_rl_vlc[0], 
+                   TEX_VLC_BITS, 2);
+    handle_vlc:
+#ifdef VLC_DEBUG
+        printf("run=%d level=%d\n", run, level);
+#endif
+        if (level == 256) {
+            if (re_index > last_index) {
+            cannot_read:
+                /* put position before read code */
+                re_index = last_re_index;
+                mb->eob_reached[j] = 0;
+                break;
+            }
+            /* EOB */
+            mb->eob_reached[j] = 1;
+            break;
+        } else if (level != 0) {
+            if ((re_index + 1) > last_index)
+                goto cannot_read;
+            sign = SHOW_SBITS(re, &s->gb, 1);
+            level = (level ^ sign) - sign;
+            LAST_SKIP_BITS(re, &s->gb, 1);
+            pos += run;
+            /* error */
+            if (pos >= 64) {
+                goto read_error;
+            }
+            pos1 = scan_table[pos];
+            level = level << shift_table[pos1];
+            block[pos1] = level;
+            //            printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]);
+        } else {
+            if (re_index > last_index)
+                goto cannot_read;
+            /* level is zero: means run without coding. No
+               sign is coded */
+            pos += run;
+            /* error */
+            if (pos >= 64) {
+            read_error:
+#if defined(VLC_DEBUG) || 1
+                printf("error pos=%d\n", pos);
+#endif
+                /* for errors, we consider the eob is reached */
+                mb->eob_reached[j] = 1;
+                break;
+            }
+        }
+    }
+    CLOSE_READER(re, &s->gb);
+    mb->pos[j] = pos;
+}
+
+static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left)
+{
+    while (bits_left >= 16) {
+        put_bits(pb, 16, get_bits(gb, 16));
+        bits_left -= 16;
+    }
+    if (bits_left > 0) {
+        put_bits(pb, bits_left, get_bits(gb, bits_left));
+    }
+}
+
+/* mb_x and mb_y are in units of 8 pixels */
+static inline void dv_decode_video_segment(DVVideoDecodeContext *s, 
+                                           UINT8 *buf_ptr1, 
+                                           const UINT16 *mb_pos_ptr)
+{
+    int quant, dc, dct_mode, class1, j;
+    int mb_index, mb_x, mb_y, v, last_index;
+    DCTELEM *block, *block1;
+    int c_offset, bits_left;
+    UINT8 *y_ptr;
+    MBInfo mb_data[5], *mb;
+    void (*idct_put)(UINT8 *dest, int line_size, DCTELEM *block);
+    UINT8 *buf_ptr;
+    PutBitContext pb, vs_pb;
+    UINT8 vs_bit_buffer[5 * 80 + 4];
+    int vs_bit_count;
+    
+    memset(s->block, 0, sizeof(s->block));
+
+    /* pass 1 : read DC and AC coefficients in blocks */
+    buf_ptr = buf_ptr1;
+    block1 = &s->block[0][0];
+    mb = mb_data;
+    init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80, NULL, NULL);
+    vs_bit_count = 0;
+    for(mb_index = 0; mb_index < 5; mb_index++) {
+        /* skip header */
+        quant = buf_ptr[3] & 0x0f;
+        buf_ptr += 4;
+        init_put_bits(&pb, mb->bit_buffer, 80, NULL, NULL);
+        mb->bits_left = 0;
+        block = block1;
+        for(j = 0;j < 6; j++) {
+            /* NOTE: size is not important here */
+            init_get_bits(&s->gb, buf_ptr, 14);
+            
+            /* get the dc */
+            dc = get_bits(&s->gb, 9);
+            dc = (dc << (32 - 9)) >> (32 - 9);
+            dct_mode = get_bits1(&s->gb);
+            mb->dct_mode[j] = dct_mode;
+            mb->scan_table[j] = s->dv_zigzag[dct_mode];
+            class1 = get_bits(&s->gb, 2);
+            mb->shift_table[j] = s->dv_shift[dct_mode][class1 == 3]
+                [quant + dv_quant_offset[class1]];
+            dc = dc << 2;
+            /* convert to unsigned because 128 is not added in the
+               standard IDCT */
+            dc += 1024;
+            block[0] = dc;
+            last_index = block_sizes[j];
+            buf_ptr += last_index >> 3;
+            mb->pos[j] = 0;
+            mb->partial_bit_count[j] = 0;
+
+            dv_decode_ac(s, mb, block, j, last_index);
+
+            /* write the remaining bits  in a new buffer only if the
+               block is finished */
+            bits_left = last_index - s->gb.index;
+            if (mb->eob_reached[j]) {
+                mb->partial_bit_count[j] = 0;
+                mb->bits_left += bits_left;
+                bit_copy(&pb, &s->gb, bits_left);
+            } else {
+                /* should be < 16 bits otherwise a codeword could have
+                   been parsed */
+                mb->partial_bit_count[j] = bits_left;
+                mb->partial_bit_buffer[j] = get_bits(&s->gb, bits_left);
+            }
+            block += 64;
+        }
+        
+        flush_put_bits(&pb);
+
+        /* pass 2 : we can do it just after */
+#ifdef VLC_DEBUG
+        printf("***pass 2 size=%d\n", mb->bits_left);
+#endif
+        block = block1;
+        init_get_bits(&s->gb, mb->bit_buffer, 80);
+        for(j = 0;j < 6; j++) {
+            if (!mb->eob_reached[j] && s->gb.index < mb->bits_left) {
+                dv_decode_ac(s, mb, block, j, mb->bits_left);
+                /* if still not finished, no need to parse other blocks */
+                if (!mb->eob_reached[j]) {
+                    /* we could not parse the current AC coefficient,
+                       so we add the remaining bytes */
+                    bits_left = mb->bits_left - s->gb.index;
+                    if (bits_left > 0) {
+                        mb->partial_bit_count[j] += bits_left;
+                        mb->partial_bit_buffer[j] = 
+                            (mb->partial_bit_buffer[j] << bits_left) | 
+                            get_bits(&s->gb, bits_left);
+                    }
+                    goto next_mb;
+                }
+            }
+            block += 64;
+        }
+        /* all blocks are finished, so the extra bytes can be used at
+           the video segment level */
+        bits_left = mb->bits_left - s->gb.index;
+        vs_bit_count += bits_left;
+        bit_copy(&vs_pb, &s->gb, bits_left);
+    next_mb:
+        mb++;
+        block1 += 6 * 64;
+    }
+
+    /* we need a pass other the whole video segment */
+    flush_put_bits(&vs_pb);
+        
+#ifdef VLC_DEBUG
+    printf("***pass 3 size=%d\n", vs_bit_count);
+#endif
+    block = &s->block[0][0];
+    mb = mb_data;
+    init_get_bits(&s->gb, vs_bit_buffer, 5 * 80);
+    for(mb_index = 0; mb_index < 5; mb_index++) {
+        for(j = 0;j < 6; j++) {
+            if (!mb->eob_reached[j]) {
+#ifdef VLC_DEBUG
+                printf("start %d:%d\n", mb_index, j);
+#endif
+                dv_decode_ac(s, mb, block, j, vs_bit_count);
+            }
+            block += 64;
+        }
+        mb++;
+    }
+    
+    /* compute idct and place blocks */
+    block = &s->block[0][0];
+    mb = mb_data;
+    for(mb_index = 0; mb_index < 5; mb_index++) {
+        v = *mb_pos_ptr++;
+        mb_x = v & 0xff;
+        mb_y = v >> 8;
+        y_ptr = s->current_picture[0] + (mb_y * s->linesize[0] * 8) + (mb_x * 8);
+        if (s->sampling_411)
+            c_offset = (mb_y * s->linesize[1] * 8) + ((mb_x >> 2) * 8);
+        else
+            c_offset = ((mb_y >> 1) * s->linesize[1] * 8) + ((mb_x >> 1) * 8);
+        for(j = 0;j < 6; j++) {
+            idct_put = s->idct_put[mb->dct_mode[j]];
+            if (j < 4) {
+                if (s->sampling_411) {
+                    idct_put(y_ptr + (j * 8), s->linesize[0], block);
+                } else {
+                    idct_put(y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->linesize[0]),
+                             s->linesize[0], block);
+                }
+            } else {
+                /* don't ask me why they inverted Cb and Cr ! */
+                idct_put(s->current_picture[6 - j] + c_offset, 
+                         s->linesize[6 - j], block);
+            }
+            block += 64;
+        }
+        mb++;
+    }
+}
+
+
+/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
+   144000 bytes for PAL) */
+static int dvvideo_decode_frame(AVCodecContext *avctx, 
+                                 void *data, int *data_size,
+                                 UINT8 *buf, int buf_size)
+{
+    DVVideoDecodeContext *s = avctx->priv_data;
+    int sct, dsf, apt, ds, nb_dif_segs, vs, size, width, height, i;
+    UINT8 *buf_ptr;
+    const UINT16 *mb_pos_ptr;
+    AVPicture *picture;
+    
+    /* parse id */
+    init_get_bits(&s->gb, buf, buf_size);
+    sct = get_bits(&s->gb, 3);
+    if (sct != 0)
+        return -1;
+    skip_bits(&s->gb, 5);
+    get_bits(&s->gb, 4); /* dsn (sequence number */
+    get_bits(&s->gb, 1); /* fsc (channel number) */
+    skip_bits(&s->gb, 3);
+    get_bits(&s->gb, 8); /* dbn (diff block number 0-134) */
+
+    dsf = get_bits(&s->gb, 1); /* 0 = NTSC 1 = PAL */
+    if (get_bits(&s->gb, 1) != 0)
+        return -1;
+    skip_bits(&s->gb, 11);
+    apt = get_bits(&s->gb, 3); /* apt */
+
+    get_bits(&s->gb, 1); /* tf1 */
+    skip_bits(&s->gb, 4);
+    get_bits(&s->gb, 3); /* ap1 */
+
+    get_bits(&s->gb, 1); /* tf2 */
+    skip_bits(&s->gb, 4);
+    get_bits(&s->gb, 3); /* ap2 */
+
+    get_bits(&s->gb, 1); /* tf3 */
+    skip_bits(&s->gb, 4);
+    get_bits(&s->gb, 3); /* ap3 */
+    
+    /* init size */
+    width = 720;
+    if (dsf) {
+        if (buf_size != PAL_FRAME_SIZE)
+            return -1;
+        height = 576;
+        nb_dif_segs = 12;
+    } else {
+        if (buf_size != NTSC_FRAME_SIZE)
+            return -1;
+        height = 480;
+        nb_dif_segs = 10;
+    }
+
+    /* (re)alloc picture if needed */
+    if (s->width != width || s->height != height) {
+        for(i=0;i<3;i++)
+            av_freep(&s->current_picture[i]);
+        for(i=0;i<3;i++) {
+            size = width * height;
+            s->linesize[i] = width;
+            if (i >= 1) {
+                size >>= 2;
+                s->linesize[i] >>= 1;
+            }
+            s->current_picture[i] = av_malloc(size);
+            if (!s->current_picture[i])
+                return -1;
+        }
+        s->width = width;
+        s->height = height;
+    }
+
+    /* XXX: is it correct to assume that 420 is always used in PAL
+       mode ? */
+    s->sampling_411 = !dsf;
+    if (s->sampling_411)
+        mb_pos_ptr = dv_place_411;
+    else
+        mb_pos_ptr = dv_place_420;
+    
+    /* for each DIF segment */
+    buf_ptr = buf;
+    for (ds = 0; ds < nb_dif_segs; ds++) {
+        buf_ptr += 6 * 80; /* skip DIF segment header */
+        
+        for(vs = 0; vs < 27; vs++) {
+            if ((vs % 3) == 0) {
+                /* skip audio block */
+                buf_ptr += 80;
+            }
+            dv_decode_video_segment(s, buf_ptr, mb_pos_ptr);
+            buf_ptr += 5 * 80;
+            mb_pos_ptr += 5;
+        }
+    }
+
+    /* return image */
+    avctx->width = width;
+    avctx->height = height;
+    if (s->sampling_411)
+        avctx->pix_fmt = PIX_FMT_YUV420P; /* XXX: incorrect, add PIX_FMT_YUV411P */
+    else
+        avctx->pix_fmt = PIX_FMT_YUV420P;
+    if (dsf)
+        avctx->frame_rate = 25 * FRAME_RATE_BASE;
+    else
+        avctx->frame_rate = 30 * FRAME_RATE_BASE;
+    *data_size = sizeof(AVPicture);
+    picture = data;
+    for(i=0;i<3;i++) {
+        picture->data[i] = s->current_picture[i];
+        picture->linesize[i] = s->linesize[i];
+    }
+    return buf_size;
+}
+
+static int dvvideo_decode_end(AVCodecContext *avctx)
+{
+    DVVideoDecodeContext *s = avctx->priv_data;
+    int i;
+
+    for(i=0;i<3;i++)
+        av_freep(&s->current_picture[i]);
+    return 0;
+}
+
+AVCodec dvvideo_decoder = {
+    "dvvideo",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_DVVIDEO,
+    sizeof(DVVideoDecodeContext),
+    dvvideo_decode_init,
+    NULL,
+    dvvideo_decode_end,
+    dvvideo_decode_frame,
+    0,
+    NULL
+};
+
+typedef struct DVAudioDecodeContext {
+    AVCodecContext *avctx;
+    GetBitContext gb;
+
+} DVAudioDecodeContext;
+
+static int dvaudio_decode_init(AVCodecContext *avctx)
+{
+    //    DVAudioDecodeContext *s = avctx->priv_data;
+    return 0;
+}
+
+/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
+   144000 bytes for PAL) */
+static int dvaudio_decode_frame(AVCodecContext *avctx, 
+                                 void *data, int *data_size,
+                                 UINT8 *buf, int buf_size)
+{
+    //    DVAudioDecodeContext *s = avctx->priv_data;
+    return buf_size;
+}
+
+static int dvaudio_decode_end(AVCodecContext *avctx)
+{
+    //    DVAudioDecodeContext *s = avctx->priv_data;
+    return 0;
+}
+
+AVCodec dvaudio_decoder = {
+    "dvaudio",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_DVAUDIO,
+    sizeof(DVAudioDecodeContext),
+    dvaudio_decode_init,
+    NULL,
+    dvaudio_decode_end,
+    dvaudio_decode_frame,
+    0,
+    NULL
+};