Merge commit '7e42d5f0ab2aeac811fd01e122627c9198b13f01'

[ffmpeg] / libavcodec / cbs_mpeg2.c

diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c
index bfb64a0851192d555768cba9dfcafe3f6c3cdd0d..8b8b2665631edbeaa2c5f81cc9fefab1db49749e 100644 (file)
--- a/libavcodec/cbs_mpeg2.c
+++ b/libavcodec/cbs_mpeg2.c
@@ -38,24 +38,29 @@
 #define FUNC_MPEG2(rw, name) FUNC_NAME(rw, mpeg2, name)
 #define FUNC(name) FUNC_MPEG2(READWRITE, name)
 
+#define SUBSCRIPTS(subs, ...) (subs > 0 ? ((int[subs + 1]){ subs, __VA_ARGS__ }) : NULL)
+
+#define ui(width, name) \
+        xui(width, name, current->name, 0)
+#define uis(width, name, subs, ...) \
+        xui(width, name, current->name, subs, __VA_ARGS__)
+
 
 #define READ
 #define READWRITE read
 #define RWContext GetBitContext
 
-#define xui(width, name, var) do { \
+#define xui(width, name, var, subs, ...) do { \
         uint32_t value = 0; \
         CHECK(ff_cbs_read_unsigned(ctx, rw, width, #name, \
+                                   SUBSCRIPTS(subs, __VA_ARGS__), \
                                    &value, 0, (1 << width) - 1)); \
         var = value; \
     } while (0)
 
-#define ui(width, name) \
-        xui(width, name, current->name)
-
 #define marker_bit() do { \
         av_unused uint32_t one; \
-        CHECK(ff_cbs_read_unsigned(ctx, rw, 1, "marker_bit", &one, 1, 1)); \
+        CHECK(ff_cbs_read_unsigned(ctx, rw, 1, "marker_bit", NULL, &one, 1, 1)); \
     } while (0)
 
 #define nextbits(width, compare, var) \
@@ -68,7 +73,6 @@
 #undef READWRITE
 #undef RWContext
 #undef xui
-#undef ui
 #undef marker_bit
 #undef nextbits
 
@@ -77,16 +81,14 @@
 #define READWRITE write
 #define RWContext PutBitContext
 
-#define xui(width, name, var) do { \
+#define xui(width, name, var, subs, ...) do { \
         CHECK(ff_cbs_write_unsigned(ctx, rw, width, #name, \
+                                    SUBSCRIPTS(subs, __VA_ARGS__), \
                                     var, 0, (1 << width) - 1)); \
     } while (0)
 
-#define ui(width, name) \
-        xui(width, name, current->name)
-
 #define marker_bit() do { \
-        CHECK(ff_cbs_write_unsigned(ctx, rw, 1, "marker_bit", 1, 1, 1)); \
+        CHECK(ff_cbs_write_unsigned(ctx, rw, 1, "marker_bit", NULL, 1, 1, 1)); \
     } while (0)
 
 #define nextbits(width, compare, var) (var)
@@ -97,7 +99,6 @@
 #undef READWRITE
 #undef RWContext
 #undef xui
-#undef ui
 #undef marker_bit
 #undef nextbits
 
@@ -146,18 +147,12 @@ static int cbs_mpeg2_split_fragment(CodedBitstreamContext *ctx,
             unit_size = (end - 4) - (start - 1);
         }
 
-        unit_data = av_malloc(unit_size + AV_INPUT_BUFFER_PADDING_SIZE);
-        if (!unit_data)
-            return AVERROR(ENOMEM);
-        memcpy(unit_data, start - 1, unit_size);
-        memset(unit_data + unit_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
+        unit_data = (uint8_t *)start - 1;
 
         err = ff_cbs_insert_unit_data(ctx, frag, i, unit_type,
-                                      unit_data, unit_size, NULL);
-        if (err < 0) {
-            av_freep(&unit_data);
+                                      unit_data, unit_size, frag->data_ref);
+        if (err < 0)
             return err;
-        }
 
         if (end == frag->data + frag->data_size)
             break;
@@ -197,16 +192,11 @@ static int cbs_mpeg2_read_unit(CodedBitstreamContext *ctx,
         len = unit->data_size;
 
         slice->data_size = len - pos / 8;
-        slice->data_ref  = av_buffer_alloc(slice->data_size +
-                                           AV_INPUT_BUFFER_PADDING_SIZE);
+        slice->data_ref  = av_buffer_ref(unit->data_ref);
         if (!slice->data_ref)
             return AVERROR(ENOMEM);
-        slice->data = slice->data_ref->data;
+        slice->data = unit->data + pos / 8;
 
-        memcpy(slice->data,
-               unit->data + pos / 8, slice->data_size);
-        memset(slice->data + slice->data_size, 0,
-               AV_INPUT_BUFFER_PADDING_SIZE);
         slice->data_bit_start = pos % 8;
 
     } else {
@@ -274,8 +264,6 @@ static int cbs_mpeg2_write_slice(CodedBitstreamContext *ctx,
                                  PutBitContext *pbc)
 {
     MPEG2RawSlice *slice = unit->content;
-    GetBitContext gbc;
-    size_t bits_left;
     int err;
 
     err = cbs_mpeg2_write_slice_header(ctx, pbc, &slice->header);
@@ -283,21 +271,38 @@ static int cbs_mpeg2_write_slice(CodedBitstreamContext *ctx,
         return err;
 
     if (slice->data) {
+        size_t rest = slice->data_size - (slice->data_bit_start + 7) / 8;
+        uint8_t *pos = slice->data + slice->data_bit_start / 8;
+
+        av_assert0(slice->data_bit_start >= 0 &&
+                   8 * slice->data_size > slice->data_bit_start);
+
         if (slice->data_size * 8 + 8 > put_bits_left(pbc))
             return AVERROR(ENOSPC);
 
-        init_get_bits(&gbc, slice->data, slice->data_size * 8);
-        skip_bits_long(&gbc, slice->data_bit_start);
-
-        while (get_bits_left(&gbc) > 15)
-            put_bits(pbc, 16, get_bits(&gbc, 16));
+        // First copy the remaining bits of the first byte
+        if (slice->data_bit_start % 8)
+            put_bits(pbc, 8 - slice->data_bit_start % 8,
+                     *pos++ & MAX_UINT_BITS(8 - slice->data_bit_start % 8));
+
+        if (put_bits_count(pbc) % 8 == 0) {
+            // If the writer is aligned at this point,
+            // memcpy can be used to improve performance.
+            // This is the normal case.
+            flush_put_bits(pbc);
+            memcpy(put_bits_ptr(pbc), pos, rest);
+            skip_put_bytes(pbc, rest);
+        } else {
+            // If not, we have to copy manually:
+            for (; rest > 3; rest -= 4, pos += 4)
+                put_bits32(pbc, AV_RB32(pos));
 
-        bits_left = get_bits_left(&gbc);
-        put_bits(pbc, bits_left, get_bits(&gbc, bits_left));
+            for (; rest; rest--, pos++)
+                put_bits(pbc, 8, *pos);
 
-        // Align with zeroes.
-        while (put_bits_count(pbc) % 8 != 0)
-            put_bits(pbc, 1, 0);
+            // Align with zeros
+            put_bits(pbc, 8 - put_bits_count(pbc) % 8, 0);
+        }
     }
 
     return 0;
@@ -362,7 +367,7 @@ static int cbs_mpeg2_assemble_fragment(CodedBitstreamContext *ctx,
                                        CodedBitstreamFragment *frag)
 {
     uint8_t *data;
-    size_t size, dp, sp;
+    size_t size, dp;
     int i;
 
     size = 0;
@@ -382,8 +387,8 @@ static int cbs_mpeg2_assemble_fragment(CodedBitstreamContext *ctx,
         data[dp++] = 0;
         data[dp++] = 1;
 
-        for (sp = 0; sp < unit->data_size; sp++)
-            data[dp++] = unit->data[sp];
+        memcpy(data + dp, unit->data, unit->data_size);
+        dp += unit->data_size;
     }
 
     av_assert0(dp == size);