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-rw-r--r--libavcodec/mqcenc.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/libavcodec/mqcenc.c b/libavcodec/mqcenc.c
new file mode 100644
index 0000000000..97d352be44
--- /dev/null
+++ b/libavcodec/mqcenc.c
@@ -0,0 +1,119 @@
+/*
+ * MQ-coder encoder
+ * Copyright (c) 2007 Kamil Nowosad
+ *
+ * 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
+ */
+
+/**
+ * MQ-coder encoder
+ * @file
+ * @author Kamil Nowosad
+ */
+
+#include "mqc.h"
+
+static void byteout(MqcState *mqc)
+{
+retry:
+ if (*mqc->bp == 0xff){
+ mqc->bp++;
+ *mqc->bp = mqc->c >> 20;
+ mqc->c &= 0xfffff;
+ mqc->ct = 7;
+ } else if ((mqc->c & 0x8000000)){
+ (*mqc->bp)++;
+ mqc->c &= 0x7ffffff;
+ goto retry;
+ } else{
+ mqc->bp++;
+ *mqc->bp = mqc->c >> 19;
+ mqc->c &= 0x7ffff;
+ mqc->ct = 8;
+ }
+}
+
+static void renorme(MqcState *mqc)
+{
+ do{
+ mqc->a += mqc->a;
+ mqc->c += mqc->c;
+ if (!--mqc->ct)
+ byteout(mqc);
+ } while (!(mqc->a & 0x8000));
+}
+
+static void setbits(MqcState *mqc)
+{
+ int tmp = mqc->c + mqc->a;
+ mqc->c |= 0xffff;
+ if (mqc->c >= tmp)
+ mqc->c -= 0x8000;
+}
+
+void ff_mqc_initenc(MqcState *mqc, uint8_t *bp)
+{
+ ff_mqc_init_contexts(mqc);
+ mqc->a = 0x8000;
+ mqc->c = 0;
+ mqc->bp = bp-1;
+ mqc->bpstart = bp;
+ mqc->ct = 12 + (*mqc->bp == 0xff);
+}
+
+void ff_mqc_encode(MqcState *mqc, uint8_t *cxstate, int d)
+{
+ int qe;
+
+ qe = ff_mqc_qe[*cxstate];
+ mqc->a -= qe;
+ if ((*cxstate & 1) == d){
+ if (!(mqc->a & 0x8000)){
+ if (mqc->a < qe)
+ mqc->a = qe;
+ else
+ mqc->c += qe;
+ *cxstate = ff_mqc_nmps[*cxstate];
+ renorme(mqc);
+ } else
+ mqc->c += qe;
+ } else{
+ if (mqc->a < qe)
+ mqc->c += qe;
+ else
+ mqc->a = qe;
+ *cxstate = ff_mqc_nlps[*cxstate];
+ renorme(mqc);
+ }
+}
+
+int ff_mqc_length(MqcState *mqc)
+{
+ return mqc->bp - mqc->bpstart;
+}
+
+int ff_mqc_flush(MqcState *mqc)
+{
+ setbits(mqc);
+ mqc->c = mqc->c << mqc->ct;
+ byteout(mqc);
+ mqc->c = mqc->c << mqc->ct;
+ byteout(mqc);
+ if (*mqc->bp != 0xff)
+ mqc->bp++;
+ return mqc->bp - mqc->bpstart;
+}