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Diffstat (limited to 'src/3rdparty/libwebp/src/utils/bit_writer.c')
-rw-r--r--src/3rdparty/libwebp/src/utils/bit_writer.c64
1 files changed, 38 insertions, 26 deletions
diff --git a/src/3rdparty/libwebp/src/utils/bit_writer.c b/src/3rdparty/libwebp/src/utils/bit_writer.c
index 9875ca6..0644286 100644
--- a/src/3rdparty/libwebp/src/utils/bit_writer.c
+++ b/src/3rdparty/libwebp/src/utils/bit_writer.c
@@ -140,19 +140,20 @@ int VP8PutBitUniform(VP8BitWriter* const bw, int bit) {
return bit;
}
-void VP8PutValue(VP8BitWriter* const bw, int value, int nb_bits) {
- int mask;
- for (mask = 1 << (nb_bits - 1); mask; mask >>= 1)
+void VP8PutBits(VP8BitWriter* const bw, uint32_t value, int nb_bits) {
+ uint32_t mask;
+ assert(nb_bits > 0 && nb_bits < 32);
+ for (mask = 1u << (nb_bits - 1); mask; mask >>= 1)
VP8PutBitUniform(bw, value & mask);
}
-void VP8PutSignedValue(VP8BitWriter* const bw, int value, int nb_bits) {
+void VP8PutSignedBits(VP8BitWriter* const bw, int value, int nb_bits) {
if (!VP8PutBitUniform(bw, value != 0))
return;
if (value < 0) {
- VP8PutValue(bw, ((-value) << 1) | 1, nb_bits + 1);
+ VP8PutBits(bw, ((-value) << 1) | 1, nb_bits + 1);
} else {
- VP8PutValue(bw, value << 1, nb_bits + 1);
+ VP8PutBits(bw, value << 1, nb_bits + 1);
}
}
@@ -171,7 +172,7 @@ int VP8BitWriterInit(VP8BitWriter* const bw, size_t expected_size) {
}
uint8_t* VP8BitWriterFinish(VP8BitWriter* const bw) {
- VP8PutValue(bw, 0, 9 - bw->nb_bits_);
+ VP8PutBits(bw, 0, 9 - bw->nb_bits_);
bw->nb_bits_ = 0; // pad with zeroes
Flush(bw);
return bw->buf_;
@@ -201,10 +202,6 @@ void VP8BitWriterWipeOut(VP8BitWriter* const bw) {
// when extra space is needed.
#define MIN_EXTRA_SIZE (32768ULL)
-#define VP8L_WRITER_BYTES ((int)sizeof(vp8l_wtype_t))
-#define VP8L_WRITER_BITS (VP8L_WRITER_BYTES * 8)
-#define VP8L_WRITER_MAX_BITS (8 * (int)sizeof(vp8l_atype_t))
-
// Returns 1 on success.
static int VP8LBitWriterResize(VP8LBitWriter* const bw, size_t extra_size) {
uint8_t* allocated_buf;
@@ -242,33 +239,49 @@ int VP8LBitWriterInit(VP8LBitWriter* const bw, size_t expected_size) {
return VP8LBitWriterResize(bw, expected_size);
}
-void VP8LBitWriterDestroy(VP8LBitWriter* const bw) {
+void VP8LBitWriterWipeOut(VP8LBitWriter* const bw) {
if (bw != NULL) {
WebPSafeFree(bw->buf_);
memset(bw, 0, sizeof(*bw));
}
}
-void VP8LWriteBits(VP8LBitWriter* const bw, int n_bits, uint32_t bits) {
+void VP8LPutBitsFlushBits(VP8LBitWriter* const bw) {
+ // If needed, make some room by flushing some bits out.
+ if (bw->cur_ + VP8L_WRITER_BYTES > bw->end_) {
+ const uint64_t extra_size = (bw->end_ - bw->buf_) + MIN_EXTRA_SIZE;
+ if (extra_size != (size_t)extra_size ||
+ !VP8LBitWriterResize(bw, (size_t)extra_size)) {
+ bw->cur_ = bw->buf_;
+ bw->error_ = 1;
+ return;
+ }
+ }
+ *(vp8l_wtype_t*)bw->cur_ = (vp8l_wtype_t)WSWAP((vp8l_wtype_t)bw->bits_);
+ bw->cur_ += VP8L_WRITER_BYTES;
+ bw->bits_ >>= VP8L_WRITER_BITS;
+ bw->used_ -= VP8L_WRITER_BITS;
+}
+
+void VP8LPutBitsInternal(VP8LBitWriter* const bw, uint32_t bits, int n_bits) {
assert(n_bits <= 32);
// That's the max we can handle:
- assert(bw->used_ + n_bits <= 2 * VP8L_WRITER_MAX_BITS);
+ assert(sizeof(vp8l_wtype_t) == 2);
if (n_bits > 0) {
- // Local field copy.
vp8l_atype_t lbits = bw->bits_;
int used = bw->used_;
// Special case of overflow handling for 32bit accumulator (2-steps flush).
- if (VP8L_WRITER_BITS == 16) {
- if (used + n_bits >= VP8L_WRITER_MAX_BITS) {
- // Fill up all the VP8L_WRITER_MAX_BITS so it can be flushed out below.
- const int shift = VP8L_WRITER_MAX_BITS - used;
- lbits |= (vp8l_atype_t)bits << used;
- used = VP8L_WRITER_MAX_BITS;
- n_bits -= shift;
- bits >>= shift;
- assert(n_bits <= VP8L_WRITER_MAX_BITS);
- }
+#if VP8L_WRITER_BITS == 16
+ if (used + n_bits >= VP8L_WRITER_MAX_BITS) {
+ // Fill up all the VP8L_WRITER_MAX_BITS so it can be flushed out below.
+ const int shift = VP8L_WRITER_MAX_BITS - used;
+ lbits |= (vp8l_atype_t)bits << used;
+ used = VP8L_WRITER_MAX_BITS;
+ n_bits -= shift;
+ bits >>= shift;
+ assert(n_bits <= VP8L_WRITER_MAX_BITS);
}
+#endif
// If needed, make some room by flushing some bits out.
while (used >= VP8L_WRITER_BITS) {
if (bw->cur_ + VP8L_WRITER_BYTES > bw->end_) {
@@ -285,7 +298,6 @@ void VP8LWriteBits(VP8LBitWriter* const bw, int n_bits, uint32_t bits) {
lbits >>= VP8L_WRITER_BITS;
used -= VP8L_WRITER_BITS;
}
- // Eventually, insert new bits.
bw->bits_ = lbits | ((vp8l_atype_t)bits << used);
bw->used_ = used + n_bits;
}