Split the mpeg4 encoder and decoder off h263.c

Originally committed as revision 21079 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 178 insertions, 0 deletions

diff --git a/libavcodec/h263.h b/libavcodec/h263.h
new file mode 100644
index 0000000000..9c98e5e575
--- /dev/null
+++ b/libavcodec/h263.h
@@ -0,0 +1,178 @@
+/*
+ * H263 internal header
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#ifndef AVCODEC_H263_H
+#define AVCODEC_H263_H
+
+// The defines below define the number of bits that are read at once for
+// reading vlc values. Changing these may improve speed and data cache needs
+// be aware though that decreasing them may need the number of stages that is
+// passed to get_vlc* to be increased.
+#define INTRA_MCBPC_VLC_BITS 6
+#define INTER_MCBPC_VLC_BITS 7
+#define CBPY_VLC_BITS 6
+#define TEX_VLC_BITS 9
+
+extern const AVRational ff_h263_pixel_aspect[16];
+extern const uint8_t cbpy_tab[16][2];
+
+extern const uint8_t mvtab[33][2];
+
+extern const uint8_t intra_MCBPC_code[9];
+extern const uint8_t intra_MCBPC_bits[9];
+
+extern const uint8_t inter_MCBPC_code[28];
+extern const uint8_t inter_MCBPC_bits[28];
+
+extern VLC intra_MCBPC_vlc;
+extern VLC inter_MCBPC_vlc;
+extern VLC cbpy_vlc;
+
+extern RLTable rl_inter;
+
+int h263_decode_motion(MpegEncContext * s, int pred, int f_code);
+av_const int ff_h263_aspect_to_info(AVRational aspect);
+
+static inline int h263_get_motion_length(MpegEncContext * s, int val, int f_code){
+    int l, bit_size, code;
+
+    if (val == 0) {
+        return mvtab[0][1];
+    } else {
+        bit_size = f_code - 1;
+        /* modulo encoding */
+        l= INT_BIT - 6 - bit_size;
+        val = (val<<l)>>l;
+        val--;
+        code = (val >> bit_size) + 1;
+
+        return mvtab[code][1] + 1 + bit_size;
+    }
+}
+
+static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
+    if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
+        skip_put_bits(&s->pb,
+            h263_get_motion_length(s, x, f_code)
+           +h263_get_motion_length(s, y, f_code));
+    }else{
+        ff_h263_encode_motion(s, x, f_code);
+        ff_h263_encode_motion(s, y, f_code);
+    }
+}
+
+static inline int get_p_cbp(MpegEncContext * s,
+                      DCTELEM block[6][64],
+                      int motion_x, int motion_y){
+    int cbp, i;
+
+    if(s->flags & CODEC_FLAG_CBP_RD){
+        int best_cbpy_score= INT_MAX;
+        int best_cbpc_score= INT_MAX;
+        int cbpc = (-1), cbpy= (-1);
+        const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
+        const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
+
+        for(i=0; i<4; i++){
+            int score= inter_MCBPC_bits[i + offset] * lambda;
+            if(i&1) score += s->coded_score[5];
+            if(i&2) score += s->coded_score[4];
+
+            if(score < best_cbpc_score){
+                best_cbpc_score= score;
+                cbpc= i;
+            }
+        }
+
+        for(i=0; i<16; i++){
+            int score= cbpy_tab[i ^ 0xF][1] * lambda;
+            if(i&1) score += s->coded_score[3];
+            if(i&2) score += s->coded_score[2];
+            if(i&4) score += s->coded_score[1];
+            if(i&8) score += s->coded_score[0];
+
+            if(score < best_cbpy_score){
+                best_cbpy_score= score;
+                cbpy= i;
+            }
+        }
+        cbp= cbpc + 4*cbpy;
+        if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
+            if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
+                cbp= 0;
+        }
+
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
+                s->block_last_index[i]= -1;
+                s->dsp.clear_block(s->block[i]);
+            }
+        }
+    }else{
+        cbp= 0;
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0)
+                cbp |= 1 << (5 - i);
+        }
+    }
+    return cbp;
+}
+
+static inline int get_b_cbp(MpegEncContext * s, DCTELEM block[6][64],
+                            int motion_x, int motion_y, int mb_type){
+    int cbp=0, i;
+
+    if(s->flags & CODEC_FLAG_CBP_RD){
+        int score=0;
+        const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
+
+        for(i=0; i<6; i++){
+            if(s->coded_score[i] < 0){
+                score += s->coded_score[i];
+                cbp |= 1 << (5 - i);
+            }
+        }
+
+        if(cbp){
+            int zero_score= -6;
+            if ((motion_x | motion_y | s->dquant | mb_type) == 0){
+                zero_score-= 4; //2*MV + mb_type + cbp bit
+            }
+
+            zero_score*= lambda;
+            if(zero_score <= score){
+                cbp=0;
+            }
+        }
+
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
+                s->block_last_index[i]= -1;
+                s->dsp.clear_block(s->block[i]);
+            }
+        }
+    }else{
+        for (i = 0; i < 6; i++) {
+            if (s->block_last_index[i] >= 0)
+                cbp |= 1 << (5 - i);
+        }
+    }
+    return cbp;
+}
+#endif