* preAlpha DV encoding support -- there's still a truckload

      of work to do, but it least people can try it out and share
      ideas. Please don't hesitate to give it a spin:

         $ ffmpeg -i file.avi file.dv

      is all you need.

    * fix for a deallocation bug in DV muxer

Originally committed as revision 2327 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 370 insertions, 8 deletions

diff --git a/libavcodec/dv.c b/libavcodec/dv.c
index 4281267f60..b9a39965c4 100644
--- a/libavcodec/dv.c
+++ b/libavcodec/dv.c
@@ -2,6 +2,12 @@
  * DV decoder
  * Copyright (c) 2002 Fabrice Bellard.
  *
+ * DV encoder 
+ * Copyright (c) 2003 Roman Shaposhnik.
+ *
+ * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
+ * of DV technical info.
+ *
  * 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
@@ -19,7 +25,7 @@
 
 /**
  * @file dv.c
- * DV decoder.
+ * DV codec.
  */
 #include "avcodec.h"
 #include "dsputil.h"
@@ -72,7 +78,7 @@ static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
     }
 }
 
-static int dvvideo_decode_init(AVCodecContext *avctx)
+static int dvvideo_init(AVCodecContext *avctx)
 {
     DVVideoDecodeContext *s = avctx->priv_data;
     MpegEncContext s2;
@@ -140,6 +146,10 @@ static int dvvideo_decode_init(AVCodecContext *avctx)
     /* XXX: do it only for constant case */
     dv_build_unquantize_tables(s);
 
+    /* FIXME: I really don't think this should be here */
+    if (dv_codec_profile(avctx))
+	avctx->pix_fmt = dv_codec_profile(avctx)->pix_fmt; 
+    
     return 0;
 }
 
@@ -368,6 +378,9 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
             mb->pos = 0;
             mb->partial_bit_count = 0;
 
+#ifdef VLC_DEBUG
+            printf("MB block: %d, %d ", mb_index, j);
+#endif
             dv_decode_ac(s, mb, block, last_index);
 
             /* write the remaining bits  in a new buffer only if the
@@ -391,7 +404,7 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
 
         /* pass 2 : we can do it just after */
 #ifdef VLC_DEBUG
-        printf("***pass 2 size=%d\n", mb_bit_count);
+        printf("***pass 2 size=%d MB#=%d\n", mb_bit_count, mb_index);
 #endif
         block = block1;
         mb = mb1;
@@ -501,6 +514,317 @@ static inline void dv_decode_video_segment(DVVideoDecodeContext *s,
     }
 }
 
+/* Converts run and level (where level != 0) pair into vlc, returning bit size */
+static inline int dv_rl2vlc(int run, int l, uint32_t* vlc)
+{
+    int sign = l >> 8;
+    int level = (l ^ sign) - sign;
+    int size;
+    
+    sign = (sign & 1);
+
+    if (run < 15 && level < 23 && dv_vlc_codes[run][level] != -1) {
+        *vlc = (dv_vlc_bits[dv_vlc_codes[run][level]] << 1) | sign; 
+	size = dv_vlc_len[dv_vlc_codes[run][level]] + 1;
+    }
+    else { 
+	if (level < 23) {
+	    *vlc = (dv_vlc_bits[dv_vlc_codes[0][level]] << 1) | sign; 
+	    size = dv_vlc_len[dv_vlc_codes[0][level]] + 1;
+	} else {
+	    *vlc = 0xfe00 | (level << 1) | sign;
+	    size = 16;
+	}
+
+	switch(run) {
+	case 0:
+	    break;
+	case 1:
+	case 2:
+	    *vlc |= ((0x7ce | (run - 1)) << size);
+	    size += 11;
+	    break;
+	case 3:
+	case 4:
+	case 5:
+	case 6:
+	    *vlc |= ((0xfac | (run - 3)) << size);
+	    size += 12;
+	    break;
+	default:
+	    *vlc |= ((0x1f80 | (run - 1)) << size);
+	    size += 13;
+	    break;
+	}
+    }
+    
+    return size;
+}
+
+typedef struct EncBlockInfo {
+    int qno;
+    int cno;
+    int dct_mode;
+    int block_size;
+    DCTELEM *mb;
+    PutBitContext pb;
+} EncBlockInfo;
+
+static inline int dv_bits_left(EncBlockInfo* bi)
+{
+    return (bi->block_size - get_bit_count(&bi->pb));
+}
+
+static inline void dv_encode_ac(EncBlockInfo* bi, PutBitContext* heap)
+{
+    int i, level, size, run = 0;
+    uint32_t vlc;
+    PutBitContext* cpb = &bi->pb;
+    
+    for (i=1; i<64; i++) {
+       level = bi->mb[ff_zigzag_direct[i]] / 
+               (1<<(dv_quant_shifts[bi->qno + dv_quant_offset[bi->cno]]
+			       [dv_88_areas[ff_zigzag_direct[i]]] + 4 + (bi->cno == 3)));
+       if (level != 0) {
+	   size = dv_rl2vlc(run, level, &vlc);
+put_vlc:
+
+#ifdef VLC_DEBUG
+           printf(" %3d:%3d", run, level);
+#endif
+	   if (cpb == &bi->pb && size > dv_bits_left(bi)) {
+	       size -= dv_bits_left(bi);
+	       put_bits(cpb, dv_bits_left(bi), vlc >> size);
+	       vlc = vlc & ((1<<size)-1);
+	       cpb = heap;
+	   }
+	   put_bits(cpb, size, vlc);
+	   run = 0;
+       } else
+	   run++;
+    }
+   
+    if (i == 64) {
+        size = 4; vlc = 6; /* End Of Block stamp */
+	goto put_vlc;
+    }
+}
+
+static inline void dv_redistr_bits(EncBlockInfo* bi, int count, uint8_t* extra_data, int extra_bits, PutBitContext* heap)
+{
+    int i;
+    GetBitContext gb;
+    
+    init_get_bits(&gb, extra_data, extra_bits);
+    
+    for (i=0; i<count; i++) {
+       int bits_left = dv_bits_left(bi);
+#ifdef VLC_DEBUG
+       if (bits_left)
+           printf("------------> inserting %d bytes in %d:%d\n", bits_left, i/6, i%6);
+#endif
+       if (bits_left > extra_bits) {
+           bit_copy(&bi->pb, &gb, extra_bits); 
+	   extra_bits = 0;
+	   break;
+       } else
+           bit_copy(&bi->pb, &gb, bits_left);
+	   
+       extra_bits -= bits_left;
+       bi++;
+    }
+    
+    if (extra_bits > 0 && heap)
+	bit_copy(heap, &gb, extra_bits);
+}
+
+static inline void dv_set_class_number(EncBlockInfo* bi, int j)
+{
+    int i, max_ac = 0;
+
+    for (i=1; i<64; i++) {
+       int ac = abs(bi->mb[ff_zigzag_direct[i]]) / 4;
+       if (max_ac < ac)
+           max_ac = ac;
+    }
+    if (max_ac < 12)
+        bi->cno = j;
+    else if (max_ac < 24)
+        bi->cno = j + 1;
+    else if (max_ac < 36)
+        bi->cno = j + 2;
+    else
+        bi->cno = j + 3;
+    
+    if (bi->cno > 3)
+        bi->cno = 3;
+}
+
+/*
+ * This is a very rough initial implementaion. The performance is
+ * horrible and some features are missing, mainly 2-4-8 DCT encoding.
+ * The weighting is missing as well, but it's missing from the decoding
+ * step also -- so at least we're on the same page with decoder ;-)
+ */
+static inline void dv_encode_video_segment(DVVideoDecodeContext *s, 
+                                           uint8_t *dif, 
+                                           const uint16_t *mb_pos_ptr)
+{
+    int mb_index, i, j, v;
+    int mb_x, mb_y, c_offset, linesize; 
+    uint8_t*  y_ptr;
+    uint8_t*  data;
+    int       do_edge_wrap;
+    DCTELEM  *block;
+    EncBlockInfo  enc_blks[5*6];
+    EncBlockInfo* enc_blk;
+    int       free_vs_bits;
+    int extra_bits;
+    PutBitContext extra_vs;
+    uint8_t   extra_vs_data[5*6*128];
+    uint8_t   extra_mb_data[6*128];
+
+    int       QNO = 15;
+   
+    /* Stage 1 -- doing DCT on 5 MBs */
+    block = &s->block[0][0];
+    for(mb_index = 0; mb_index < 5; mb_index++) {
+        v = *mb_pos_ptr++;
+        mb_x = v & 0xff;
+        mb_y = v >> 8;
+        y_ptr = s->picture.data[0] + (mb_y * s->picture.linesize[0] * 8) + (mb_x * 8);
+	c_offset = (s->sys->pix_fmt == PIX_FMT_YUV411P) ?
+	           ((mb_y * s->picture.linesize[1] * 8) + ((mb_x >> 2) * 8)) :
+		   (((mb_y >> 1) * s->picture.linesize[1] * 8) + ((mb_x >> 1) * 8));
+	do_edge_wrap = 0;
+        for(j = 0;j < 6; j++) {
+            if (j < 4) {  /* Four Y blocks */
+		/* NOTE: at end of line, the macroblock is handled as 420 */
+		if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x < (704 / 8)) {
+                    data = y_ptr + (j * 8);
+                } else {
+                    data = y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->picture.linesize[0]);
+                }
+		linesize = s->picture.linesize[0];
+            } else {      /* Cr and Cb blocks */
+	        /* don't ask Fabrice why they inverted Cb and Cr ! */
+	        data = s->picture.data[6 - j] + c_offset;
+		linesize = s->picture.linesize[6 - j];
+		if (s->sys->pix_fmt == PIX_FMT_YUV411P && mb_x >= (704 / 8))
+		    do_edge_wrap = 1;
+	    }	
+            
+	    /* Everything is set up -- now just copy data -> DCT block */
+	    if (do_edge_wrap) {  /* Edge wrap copy: 4x16 -> 8x8 */
+		uint8_t* d;
+		DCTELEM *b = block;
+	        for (i=0;i<8;i++) {
+		   d = data + 8 * linesize;
+		   b[0] = data[0]; b[1] = data[1]; b[2] = data[2]; b[3] = data[3];
+                   b[4] =    d[0]; b[5] =    d[1]; b[6] =    d[2]; b[7] =    d[3];
+		   data += linesize;
+		   b += 8;
+		}
+	    } else {             /* Simple copy: 8x8 -> 8x8 */
+	        s->get_pixels(block, data, linesize);
+	    }
+            
+	    s->fdct(block);
+	    
+	    block += 64;
+        }
+    }
+
+    /* Stage 2 -- setup for encoding phase */
+    enc_blk = &enc_blks[0];
+    block = &s->block[0][0];
+    for (i=0; i<5; i++) {
+       for (j=0; j<6; j++) {
+	  enc_blk->mb = block;
+	  enc_blk->dct_mode = 0;
+	  enc_blk->block_size = block_sizes[j];
+	  
+	  dv_set_class_number(enc_blk, j/4*(j%2));
+	  
+	  block += 64;
+	  enc_blk++;
+       }
+    }
+   
+    /* Stage 3 -- encoding by trial-and-error */
+encode_vs:
+    enc_blk = &enc_blks[0];
+    for (i=0; i<5; i++) {
+       uint8_t* p = dif + i*80 + 4;
+       for (j=0; j<6; j++) {
+          enc_blk->qno = QNO;
+	  init_put_bits(&enc_blk->pb, p, block_sizes[j]/8, NULL, NULL);
+	  enc_blk++;
+	  p += block_sizes[j]/8;
+       }
+    }
+
+    init_put_bits(&extra_vs, extra_vs_data, sizeof(extra_vs_data), NULL, NULL);
+    free_vs_bits = 0;
+    enc_blk = &enc_blks[0];
+    for (i=0; i<5; i++) {
+       PutBitContext extra_mb;
+       EncBlockInfo* enc_blk2 = enc_blk;
+       int free_mb_bits = 0;
+
+       init_put_bits(&extra_mb, extra_mb_data, sizeof(extra_mb_data), NULL, NULL);
+       dif[i*80 + 3] = enc_blk->qno;
+       
+       for (j=0; j<6; j++) {
+	  uint16_t dc = ((enc_blk->mb[0] >> 3) - 1024) >> 2;
+
+	  put_bits(&enc_blk->pb, 9, dc);
+	  put_bits(&enc_blk->pb, 1, enc_blk->dct_mode);
+	  put_bits(&enc_blk->pb, 2, enc_blk->cno);
+
+#ifdef VLC_DEBUG
+          printf("[%d, %d]: ", i, j);
+#endif
+	  dv_encode_ac(enc_blk, &extra_mb);
+#ifdef VLC_DEBUG
+          printf("\n");
+#endif
+	  
+	  free_mb_bits += dv_bits_left(enc_blk);
+	  enc_blk++;
+       }
+       
+       /* We can't flush extra_mb just yet -- since it'll round up bit number */
+       extra_bits = get_bit_count(&extra_mb);
+       if (free_mb_bits > extra_bits)
+           free_vs_bits += free_mb_bits - extra_bits;
+    
+       if (extra_bits) {  /* FIXME: speed up things when free_mb_bits == 0 */
+           flush_put_bits(&extra_mb);
+           dv_redistr_bits(enc_blk2, 6, extra_mb_data, extra_bits, &extra_vs);
+       }
+    }
+    
+    /* We can't flush extra_mb just yet -- since it'll round up bit number */
+    extra_bits = get_bit_count(&extra_vs);
+    if (extra_bits > free_vs_bits && QNO) { /* FIXME: very crude trial-and-error */
+        QNO--;
+	goto encode_vs;
+    }
+    
+    if (extra_bits) {
+        flush_put_bits(&extra_vs);
+        dv_redistr_bits(&enc_blks[0], 5*6, extra_vs_data, extra_bits, NULL);
+    }
+
+    for (i=0; i<6*5; i++) {
+       flush_put_bits(&enc_blks[i].pb);
+#ifdef VLC_DEBUG
+       printf("[%d:%d] qno=%d cno=%d\n", i/6, i%6, enc_blks[i].qno, enc_blks[i].cno);
+#endif
+    }
+}
+
 /* NOTE: exactly one frame must be given (120000 bytes for NTSC,
    144000 bytes for PAL) */
 static int dvvideo_decode_frame(AVCodecContext *avctx, 
@@ -535,6 +859,9 @@ static int dvvideo_decode_frame(AVCodecContext *avctx,
             if ((vs % 3) == 0)
 	        buf += 80; /* skip audio block */
             
+#ifdef VLC_DEBUG
+            printf("********************* %d, %d **********************\n", ds, vs);
+#endif
 	    dv_decode_video_segment(s, buf, mb_pos_ptr);
             buf += 5 * 80;
             mb_pos_ptr += 5;
@@ -550,10 +877,45 @@ static int dvvideo_decode_frame(AVCodecContext *avctx,
     return s->sys->frame_size;
 }
 
-static int dvvideo_decode_end(AVCodecContext *avctx)
+static int dvvideo_encode_frame(AVCodecContext *c, uint8_t *buf, int buf_size, 
+                                void *data)
 {
-    avcodec_default_free_buffers(avctx);    
+    DVVideoDecodeContext *s = c->priv_data;
+    const uint16_t *mb_pos_ptr;
+    int ds, vs;
+
+    s->sys = dv_codec_profile(c);
+    if (!s->sys)
+	return -1;
+    
+    c->pix_fmt = s->sys->pix_fmt;
+    s->picture = *((AVFrame *)data);
+
+    /* for each DIF segment */
+    mb_pos_ptr = s->sys->video_place;
+    for (ds = 0; ds < s->sys->difseg_size; ds++) {
+        buf += 6 * 80; /* skip DIF segment header */
+        
+        for(vs = 0; vs < 27; vs++) {
+            if ((vs % 3) == 0)
+	        buf += 80; /* skip audio block */
+
+#ifdef VLC_DEBUG
+            printf("********************* %d, %d **********************\n", ds, vs);
+#endif
+	    dv_encode_video_segment(s, buf, mb_pos_ptr);
+            buf += 5 * 80;
+            mb_pos_ptr += 5;
+        }
+    }
 
+    emms_c();
+    return s->sys->frame_size;
+}
+
+static int dvvideo_end(AVCodecContext *avctx)
+{
+    avcodec_default_free_buffers(avctx);    
     return 0;
 }
 
@@ -562,9 +924,9 @@ AVCodec dvvideo_decoder = {
     CODEC_TYPE_VIDEO,
     CODEC_ID_DVVIDEO,
     sizeof(DVVideoDecodeContext),
-    dvvideo_decode_init,
-    NULL,
-    dvvideo_decode_end,
+    dvvideo_init,
+    dvvideo_encode_frame,
+    dvvideo_end,
     dvvideo_decode_frame,
     CODEC_CAP_DR1,
     NULL