dsputil: Split off IDCT bits into their own context

1 files changed, 104 insertions, 0 deletions

diff --git a/libavcodec/idctdsp.h b/libavcodec/idctdsp.h
new file mode 100644
index 0000000..e3a2317
--- /dev/null
+++ b/libavcodec/idctdsp.h
@@ -0,0 +1,104 @@
+/*
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_IDCTDSP_H
+#define AVCODEC_IDCTDSP_H
+
+#include <stdint.h>
+
+#include "avcodec.h"
+
+/**
+ * Scantable.
+ */
+typedef struct ScanTable {
+    const uint8_t *scantable;
+    uint8_t permutated[64];
+    uint8_t raster_end[64];
+} ScanTable;
+
+void ff_init_scantable(uint8_t *permutation, ScanTable *st,
+                       const uint8_t *src_scantable);
+void ff_init_scantable_permutation(uint8_t *idct_permutation,
+                                   int idct_permutation_type);
+int ff_init_scantable_permutation_x86(uint8_t *idct_permutation,
+                                      int idct_permutation_type);
+
+typedef struct IDCTDSPContext {
+    /* pixel ops : interface with DCT */
+    void (*put_pixels_clamped)(const int16_t *block /* align 16 */,
+                               uint8_t *pixels /* align 8 */,
+                               int line_size);
+    void (*put_signed_pixels_clamped)(const int16_t *block /* align 16 */,
+                                      uint8_t *pixels /* align 8 */,
+                                      int line_size);
+    void (*add_pixels_clamped)(const int16_t *block /* align 16 */,
+                               uint8_t *pixels /* align 8 */,
+                               int line_size);
+
+    void (*idct)(int16_t *block /* align 16 */);
+
+    /**
+     * block -> idct -> clip to unsigned 8 bit -> dest.
+     * (-1392, 0, 0, ...) -> idct -> (-174, -174, ...) -> put -> (0, 0, ...)
+     * @param line_size size in bytes of a horizontal line of dest
+     */
+    void (*idct_put)(uint8_t *dest /* align 8 */,
+                     int line_size, int16_t *block /* align 16 */);
+
+    /**
+     * block -> idct -> add dest -> clip to unsigned 8 bit -> dest.
+     * @param line_size size in bytes of a horizontal line of dest
+     */
+    void (*idct_add)(uint8_t *dest /* align 8 */,
+                     int line_size, int16_t *block /* align 16 */);
+
+    /**
+     * IDCT input permutation.
+     * Several optimized IDCTs need a permutated input (relative to the
+     * normal order of the reference IDCT).
+     * This permutation must be performed before the idct_put/add.
+     * Note, normally this can be merged with the zigzag/alternate scan<br>
+     * An example to avoid confusion:
+     * - (->decode coeffs -> zigzag reorder -> dequant -> reference IDCT -> ...)
+     * - (x -> reference DCT -> reference IDCT -> x)
+     * - (x -> reference DCT -> simple_mmx_perm = idct_permutation
+     *    -> simple_idct_mmx -> x)
+     * - (-> decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant
+     *    -> simple_idct_mmx -> ...)
+     */
+    uint8_t idct_permutation[64];
+    int idct_permutation_type;
+#define FF_NO_IDCT_PERM 1
+#define FF_LIBMPEG2_IDCT_PERM 2
+#define FF_SIMPLE_IDCT_PERM 3
+#define FF_TRANSPOSE_IDCT_PERM 4
+#define FF_PARTTRANS_IDCT_PERM 5
+#define FF_SSE2_IDCT_PERM 6
+} IDCTDSPContext;
+
+void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx);
+
+void ff_idctdsp_init_arm(IDCTDSPContext *c, AVCodecContext *avctx,
+                         unsigned high_bit_depth);
+void ff_idctdsp_init_ppc(IDCTDSPContext *c, AVCodecContext *avctx,
+                         unsigned high_bit_depth);
+void ff_idctdsp_init_x86(IDCTDSPContext *c, AVCodecContext *avctx,
+                         unsigned high_bit_depth);
+
+#endif /* AVCODEC_IDCTDSP_H */