Initial revision

Originally committed as revision 2 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 229 insertions, 0 deletions

diff --git a/libav/h263enc.c b/libav/h263enc.c
new file mode 100644
index 0000000000..59db1ee512
--- /dev/null
+++ b/libav/h263enc.c
@@ -0,0 +1,229 @@
+/*
+ * H263 backend for ffmpeg encoder
+ * Copyright (c) 2000 Gerard Lantau.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <netinet/in.h>
+#include "common.h"
+#include "mpegvideo.h"
+#include "h263data.h"
+
+void h263_picture_header(MpegEncContext *s, int picture_number)
+{
+    int format;
+
+    align_put_bits(&s->pb);
+    put_bits(&s->pb, 22, 0x20);
+    put_bits(&s->pb, 8, ((s->picture_number * 30) / s->frame_rate) & 0xff); 
+
+    put_bits(&s->pb, 1, 1); /* marker */
+    put_bits(&s->pb, 1, 0); /* h263 id */
+    put_bits(&s->pb, 1, 0); /* split screen off */
+    put_bits(&s->pb, 1, 0); /* camera  off */
+    put_bits(&s->pb, 1, 0); /* freeze picture release off */
+
+    if (s->width == 128 && s->height == 96)
+        format = 1;
+    else if (s->width == 176 && s->height == 144)
+        format = 2;
+    else if (s->width == 352 && s->height == 288)
+        format = 3;
+    else if (s->width == 704 && s->height == 576)
+        format = 4;
+    else if (s->width == 1408 && s->height == 1152)
+        format = 5;
+    else
+        abort();
+
+    put_bits(&s->pb, 3, format);
+    
+    put_bits(&s->pb, 1, (s->pict_type == P_TYPE));
+
+    put_bits(&s->pb, 1, 0); /* unrestricted motion vector: off */
+
+    put_bits(&s->pb, 1, 0); /* SAC: off */
+
+    put_bits(&s->pb, 1, 0); /* advanced prediction mode: off */
+
+    put_bits(&s->pb, 1, 0); /* not PB frame */
+
+    put_bits(&s->pb, 5, s->qscale);
+    
+    put_bits(&s->pb, 1, 0); /* Continuous Presence Multipoint mode: off */
+    
+    put_bits(&s->pb, 1, 0); /* no PEI */
+}
+
+static void h263_encode_block(MpegEncContext *s, DCTELEM *block, 
+                              int n);
+
+void h263_encode_mb(MpegEncContext *s, 
+                    DCTELEM block[6][64],
+                    int motion_x, int motion_y)
+{
+    int cbpc, cbpy, i, cbp;
+
+    if (!s->mb_intra) {
+        /* compute cbp */
+        cbp = 0;
+        for(i=0;i<6;i++) {
+            if (s->block_last_index[i] >= 0)
+                cbp |= 1 << (5 - i);
+        }
+        if ((cbp | motion_x | motion_y) == 0) {
+            /* skip macroblock */
+            put_bits(&s->pb, 1, 1);
+            return;
+        }
+            
+        put_bits(&s->pb, 1, 0); /* mb coded */
+        cbpc = cbp & 3;
+        put_bits(&s->pb, 
+                 inter_MCBPC_bits[cbpc], 
+                 inter_MCBPC_code[cbpc]);
+        cbpy = cbp >> 2;
+        cbpy ^= 0xf;
+        put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+        
+        /* motion vectors: zero */
+        put_bits(&s->pb, 1, 1);
+        put_bits(&s->pb, 1, 1);
+
+    } else {
+        /* compute cbp */
+        cbp = 0;
+        for(i=0;i<6;i++) {
+            if (s->block_last_index[i] >= 1)
+                cbp |= 1 << (5 - i);
+        }
+
+        cbpc = cbp & 3;
+        if (s->pict_type == I_TYPE) {
+            put_bits(&s->pb, 
+                     intra_MCBPC_bits[cbpc], 
+                     intra_MCBPC_code[cbpc]);
+        } else {
+            put_bits(&s->pb, 1, 0); /* mb coded */
+            put_bits(&s->pb, 
+                     inter_MCBPC_bits[cbpc + 4], 
+                     inter_MCBPC_code[cbpc + 4]);
+        }
+        cbpy = cbp >> 2;
+        put_bits(&s->pb, cbpy_tab[cbpy][1], cbpy_tab[cbpy][0]);
+    }
+    
+    /* encode each block */
+    for(i=0;i<6;i++) {
+        h263_encode_block(s, block[i], i);
+    }
+}
+
+static void h263_encode_block(MpegEncContext *s, DCTELEM *block, int n)
+{
+    int level, run, last, i, j, last_index, last_non_zero, sign, alevel;
+    int code, len;
+
+    if (s->mb_intra) {
+        /* DC coef */
+        level = block[0];
+        if (level == 128)
+            put_bits(&s->pb, 8, 0xff);
+        else
+            put_bits(&s->pb, 8, level & 0xff);
+        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 = zigzag_direct[i];
+        level = block[j];
+        if (level) {
+            run = i - last_non_zero - 1;
+            last = (i == last_index);
+            sign = 0;
+            alevel = level;
+            if (level < 0) {
+                sign = 1;
+                alevel = -level;
+            }
+            len = 0;
+            code = 0; /* only to disable warning */
+            if (last == 0) {
+                if (run < 2 && alevel < 13 ) {
+                    len = coeff_tab0[run][alevel-1][1];
+                    code = coeff_tab0[run][alevel-1][0];
+                } else if (run >= 2 && run < 27 && alevel < 5) {
+                    len = coeff_tab1[run-2][alevel-1][1];
+                    code = coeff_tab1[run-2][alevel-1][0];
+                }
+            } else {
+                if (run < 2 && alevel < 4) {
+                    len = coeff_tab2[run][alevel-1][1];
+                    code = coeff_tab2[run][alevel-1][0];
+                } else if (run >= 2 && run < 42 && alevel == 1) {
+                    len = coeff_tab3[run-2][1];
+                    code = coeff_tab3[run-2][0];
+                }
+            }
+            
+            if (len != 0) {
+                code = (code << 1) | sign;
+                put_bits(&s->pb, len + 1, code);
+            } else {
+                    /* escape */
+                    put_bits(&s->pb, 7, 3);
+                    put_bits(&s->pb, 1, last);
+                    put_bits(&s->pb, 6, run);
+                    put_bits(&s->pb, 8, level & 0xff);
+            }
+
+            last_non_zero = i;
+        }
+    }
+}
+
+/* write RV 1.0 compatible frame header */
+void rv10_encode_picture_header(MpegEncContext *s, int picture_number)
+{
+    align_put_bits(&s->pb);
+
+    put_bits(&s->pb, 1, 1); /* marker */
+
+    put_bits(&s->pb, 1, (s->pict_type == P_TYPE));
+
+    put_bits(&s->pb, 1, 0); /* not PB frame */
+
+    put_bits(&s->pb, 5, s->qscale);
+    
+    if (s->pict_type == I_TYPE) {
+        /* specific MPEG like DC coding not used */
+    }
+    
+    /* if multiple packets per frame are sent, the position at which
+       to display the macro blocks is coded here */
+    put_bits(&s->pb, 6, 0); /* mb_x */
+    put_bits(&s->pb, 6, 0); /* mb_y */
+    put_bits(&s->pb, 12, s->mb_width * s->mb_height);
+    
+    put_bits(&s->pb, 3, 0); /* ignored */
+}
+