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-rw-r--r--libav/h263enc.c229
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 */
+}
+
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