tta: split off hybrid filter processing as ttadsp

Signed-off-by: James Almer <jamrial@gmail.com>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 54 insertions, 0 deletions

diff --git a/libavcodec/ttadsp.c b/libavcodec/ttadsp.c
new file mode 100644
index 0000000..691824b
--- /dev/null
+++ b/libavcodec/ttadsp.c
@@ -0,0 +1,54 @@
+/*
+ * 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
+ */
+
+#include "ttadsp.h"
+
+static void ttafilter_process_dec_c(int32_t *qm, int32_t *dx, int32_t *dl,
+                                    int32_t *error, int32_t *in, int32_t shift,
+                                    int32_t round) {
+    if (*error < 0) {
+        qm[0] -= dx[0]; qm[1] -= dx[1]; qm[2] -= dx[2]; qm[3] -= dx[3];
+        qm[4] -= dx[4]; qm[5] -= dx[5]; qm[6] -= dx[6]; qm[7] -= dx[7];
+    } else if (*error > 0) {
+        qm[0] += dx[0]; qm[1] += dx[1]; qm[2] += dx[2]; qm[3] += dx[3];
+        qm[4] += dx[4]; qm[5] += dx[5]; qm[6] += dx[6]; qm[7] += dx[7];
+    }
+
+    round +=    dl[0] * qm[0] + dl[1] * qm[1] + dl[2] * qm[2] + dl[3] * qm[3] +
+                dl[4] * qm[4] + dl[5] * qm[5] + dl[6] * qm[6] + dl[7] * qm[7];
+
+    dx[0] = dx[1]; dx[1] = dx[2]; dx[2] = dx[3]; dx[3] = dx[4];
+    dl[0] = dl[1]; dl[1] = dl[2]; dl[2] = dl[3]; dl[3] = dl[4];
+
+    dx[4] = ((dl[4] >> 30) | 1);
+    dx[5] = ((dl[5] >> 30) | 2) & ~1;
+    dx[6] = ((dl[6] >> 30) | 2) & ~1;
+    dx[7] = ((dl[7] >> 30) | 4) & ~3;
+
+    *error = *in;
+    *in += (round >> shift);
+
+    dl[4] = -dl[5]; dl[5] = -dl[6];
+    dl[6] = *in - dl[7]; dl[7] = *in;
+    dl[5] += dl[6]; dl[4] += dl[5];
+}
+
+av_cold void ff_ttadsp_init(TTADSPContext *c)
+{
+    c->ttafilter_process_dec = ttafilter_process_dec_c;
+}