[FFmpeg-devel] [PATCH ε/2] lavc/h263dsp: add DCT dequantisation function

[Rémi Denis-Courmont]

---
 libavcodec/h263dsp.c | 17 +++++++++++++++++
 libavcodec/h263dsp.h |  2 ++
 2 files changed, 19 insertions(+)

diff --git a/libavcodec/h263dsp.c b/libavcodec/h263dsp.c
index 6a13353499..eb990f27bd 100644
--- a/libavcodec/h263dsp.c
+++ b/libavcodec/h263dsp.c
@@ -23,6 +23,22 @@
 #include "config.h"
 #include "h263dsp.h"
 
+static void h263_dct_unquantize_c(int16_t *block, size_t start, size_t end,
+                                  int qmul, int qadd)
+{
+    for (size_t i = start; i <= end; i++) {
+        int level = block[i];
+
+        if (level) {
+            if (level < 0)
+                level = level * qmul - qadd;
+            else
+                level = level * qmul + qadd;
+            block[i] = level;
+        }
+    }
+}
+
 const uint8_t ff_h263_loop_filter_strength[32] = {
     0, 1, 1, 2, 2, 3, 3,  4,  4,  4,  5,  5,  6,  6,  7, 7,
     7, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12
@@ -116,6 +132,7 @@ static void h263_v_loop_filter_c(uint8_t *src, int stride, int qscale)
 
 av_cold void ff_h263dsp_init(H263DSPContext *ctx)
 {
+    ctx->h263_dct_unquantize = h263_dct_unquantize_c;
     ctx->h263_h_loop_filter = h263_h_loop_filter_c;
     ctx->h263_v_loop_filter = h263_v_loop_filter_c;
 
diff --git a/libavcodec/h263dsp.h b/libavcodec/h263dsp.h
index 2dccd23392..93c128c9ac 100644
--- a/libavcodec/h263dsp.h
+++ b/libavcodec/h263dsp.h
@@ -24,6 +24,8 @@
 extern const uint8_t ff_h263_loop_filter_strength[32];
 
 typedef struct H263DSPContext {
+    void (*h263_dct_unquantize)(int16_t *block /* align 16 */, size_t offset,
+                                size_t len, int mul, int add);
     void (*h263_h_loop_filter)(uint8_t *src, int stride, int qscale);
     void (*h263_v_loop_filter)(uint8_t *src, int stride, int qscale);
 } H263DSPContext;
-- 
2.45.1