Convert .tgs with go libraries (and cgo) (telegram) (#1569)

This commit adds support for go/cgo tgs conversion when building with the -tags `cgo`
The default binaries are still "pure" go and uses the old way of converting.

* Move lottie_convert.py conversion code to its own file

* Add optional libtgsconverter

* Update vendor

* Apply suggestions from code review

* Update bridge/helper/libtgsconverter.go

Co-authored-by: Wim <wim@42.be>

1 files changed, 262 insertions, 0 deletions

diff --git a/vendor/github.com/sizeofint/webpanimation/enc_token_enc.c b/vendor/github.com/sizeofint/webpanimation/enc_token_enc.c
new file mode 100644
index 00000000..0908201b
--- /dev/null
+++ b/vendor/github.com/sizeofint/webpanimation/enc_token_enc.c
@@ -0,0 +1,262 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Paginated token buffer
+//
+//  A 'token' is a bit value associated with a probability, either fixed
+// or a later-to-be-determined after statistics have been collected.
+// For dynamic probability, we just record the slot id (idx) for the probability
+// value in the final probability array (uint8_t* probas in VP8EmitTokens).
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "enc_cost_enc.h"
+#include "enc_vp8i_enc.h"
+#include "utils_utils.h"
+
+#if !defined(DISABLE_TOKEN_BUFFER)
+
+// we use pages to reduce the number of memcpy()
+#define MIN_PAGE_SIZE 8192          // minimum number of token per page
+#define FIXED_PROBA_BIT (1u << 14)
+
+typedef uint16_t token_t;  // bit #15: bit value
+                           // bit #14: flags for constant proba or idx
+                           // bits #0..13: slot or constant proba
+struct VP8Tokens {
+  VP8Tokens* next_;        // pointer to next page
+};
+// Token data is located in memory just after the next_ field.
+// This macro is used to return their address and hide the trick.
+#define TOKEN_DATA(p) ((const token_t*)&(p)[1])
+
+//------------------------------------------------------------------------------
+
+void VP8TBufferInit(VP8TBuffer* const b, int page_size) {
+  b->tokens_ = NULL;
+  b->pages_ = NULL;
+  b->last_page_ = &b->pages_;
+  b->left_ = 0;
+  b->page_size_ = (page_size < MIN_PAGE_SIZE) ? MIN_PAGE_SIZE : page_size;
+  b->error_ = 0;
+}
+
+void VP8TBufferClear(VP8TBuffer* const b) {
+  if (b != NULL) {
+    VP8Tokens* p = b->pages_;
+    while (p != NULL) {
+      VP8Tokens* const next = p->next_;
+      WebPSafeFree(p);
+      p = next;
+    }
+    VP8TBufferInit(b, b->page_size_);
+  }
+}
+
+static int TBufferNewPage(VP8TBuffer* const b) {
+  VP8Tokens* page = NULL;
+  if (!b->error_) {
+    const size_t size = sizeof(*page) + b->page_size_ * sizeof(token_t);
+    page = (VP8Tokens*)WebPSafeMalloc(1ULL, size);
+  }
+  if (page == NULL) {
+    b->error_ = 1;
+    return 0;
+  }
+  page->next_ = NULL;
+
+  *b->last_page_ = page;
+  b->last_page_ = &page->next_;
+  b->left_ = b->page_size_;
+  b->tokens_ = (token_t*)TOKEN_DATA(page);
+  return 1;
+}
+
+//------------------------------------------------------------------------------
+
+#define TOKEN_ID(t, b, ctx) \
+    (NUM_PROBAS * ((ctx) + NUM_CTX * ((b) + NUM_BANDS * (t))))
+
+static WEBP_INLINE uint32_t AddToken(VP8TBuffer* const b, uint32_t bit,
+                                     uint32_t proba_idx,
+                                     proba_t* const stats) {
+  assert(proba_idx < FIXED_PROBA_BIT);
+  assert(bit <= 1);
+  if (b->left_ > 0 || TBufferNewPage(b)) {
+    const int slot = --b->left_;
+    b->tokens_[slot] = (bit << 15) | proba_idx;
+  }
+  VP8RecordStats(bit, stats);
+  return bit;
+}
+
+static WEBP_INLINE void AddConstantToken(VP8TBuffer* const b,
+                                         uint32_t bit, uint32_t proba) {
+  assert(proba < 256);
+  assert(bit <= 1);
+  if (b->left_ > 0 || TBufferNewPage(b)) {
+    const int slot = --b->left_;
+    b->tokens_[slot] = (bit << 15) | FIXED_PROBA_BIT | proba;
+  }
+}
+
+int VP8RecordCoeffTokens(int ctx, const struct VP8Residual* const res,
+                         VP8TBuffer* const tokens) {
+  const int16_t* const coeffs = res->coeffs;
+  const int coeff_type = res->coeff_type;
+  const int last = res->last;
+  int n = res->first;
+  uint32_t base_id = TOKEN_ID(coeff_type, n, ctx);
+  // should be stats[VP8EncBands[n]], but it's equivalent for n=0 or 1
+  proba_t* s = res->stats[n][ctx];
+  if (!AddToken(tokens, last >= 0, base_id + 0, s + 0)) {
+    return 0;
+  }
+
+  while (n < 16) {
+    const int c = coeffs[n++];
+    const int sign = c < 0;
+    const uint32_t v = sign ? -c : c;
+    if (!AddToken(tokens, v != 0, base_id + 1, s + 1)) {
+      base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 0);  // ctx=0
+      s = res->stats[VP8EncBands[n]][0];
+      continue;
+    }
+    if (!AddToken(tokens, v > 1, base_id + 2, s + 2)) {
+      base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 1);  // ctx=1
+      s = res->stats[VP8EncBands[n]][1];
+    } else {
+      if (!AddToken(tokens, v > 4, base_id + 3, s + 3)) {
+        if (AddToken(tokens, v != 2, base_id + 4, s + 4)) {
+          AddToken(tokens, v == 4, base_id + 5, s + 5);
+        }
+      } else if (!AddToken(tokens, v > 10, base_id + 6, s + 6)) {
+        if (!AddToken(tokens, v > 6, base_id + 7, s + 7)) {
+          AddConstantToken(tokens, v == 6, 159);
+        } else {
+          AddConstantToken(tokens, v >= 9, 165);
+          AddConstantToken(tokens, !(v & 1), 145);
+        }
+      } else {
+        int mask;
+        const uint8_t* tab;
+        uint32_t residue = v - 3;
+        if (residue < (8 << 1)) {          // VP8Cat3  (3b)
+          AddToken(tokens, 0, base_id + 8, s + 8);
+          AddToken(tokens, 0, base_id + 9, s + 9);
+          residue -= (8 << 0);
+          mask = 1 << 2;
+          tab = VP8Cat3;
+        } else if (residue < (8 << 2)) {   // VP8Cat4  (4b)
+          AddToken(tokens, 0, base_id + 8, s + 8);
+          AddToken(tokens, 1, base_id + 9, s + 9);
+          residue -= (8 << 1);
+          mask = 1 << 3;
+          tab = VP8Cat4;
+        } else if (residue < (8 << 3)) {   // VP8Cat5  (5b)
+          AddToken(tokens, 1, base_id + 8, s + 8);
+          AddToken(tokens, 0, base_id + 10, s + 9);
+          residue -= (8 << 2);
+          mask = 1 << 4;
+          tab = VP8Cat5;
+        } else {                         // VP8Cat6 (11b)
+          AddToken(tokens, 1, base_id + 8, s + 8);
+          AddToken(tokens, 1, base_id + 10, s + 9);
+          residue -= (8 << 3);
+          mask = 1 << 10;
+          tab = VP8Cat6;
+        }
+        while (mask) {
+          AddConstantToken(tokens, !!(residue & mask), *tab++);
+          mask >>= 1;
+        }
+      }
+      base_id = TOKEN_ID(coeff_type, VP8EncBands[n], 2);  // ctx=2
+      s = res->stats[VP8EncBands[n]][2];
+    }
+    AddConstantToken(tokens, sign, 128);
+    if (n == 16 || !AddToken(tokens, n <= last, base_id + 0, s + 0)) {
+      return 1;   // EOB
+    }
+  }
+  return 1;
+}
+
+#undef TOKEN_ID
+
+//------------------------------------------------------------------------------
+// Final coding pass, with known probabilities
+
+int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw,
+                  const uint8_t* const probas, int final_pass) {
+  const VP8Tokens* p = b->pages_;
+  assert(!b->error_);
+  while (p != NULL) {
+    const VP8Tokens* const next = p->next_;
+    const int N = (next == NULL) ? b->left_ : 0;
+    int n = b->page_size_;
+    const token_t* const tokens = TOKEN_DATA(p);
+    while (n-- > N) {
+      const token_t token = tokens[n];
+      const int bit = (token >> 15) & 1;
+      if (token & FIXED_PROBA_BIT) {
+        VP8PutBit(bw, bit, token & 0xffu);  // constant proba
+      } else {
+        VP8PutBit(bw, bit, probas[token & 0x3fffu]);
+      }
+    }
+    if (final_pass) WebPSafeFree((void*)p);
+    p = next;
+  }
+  if (final_pass) b->pages_ = NULL;
+  return 1;
+}
+
+// Size estimation
+size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas) {
+  size_t size = 0;
+  const VP8Tokens* p = b->pages_;
+  assert(!b->error_);
+  while (p != NULL) {
+    const VP8Tokens* const next = p->next_;
+    const int N = (next == NULL) ? b->left_ : 0;
+    int n = b->page_size_;
+    const token_t* const tokens = TOKEN_DATA(p);
+    while (n-- > N) {
+      const token_t token = tokens[n];
+      const int bit = token & (1 << 15);
+      if (token & FIXED_PROBA_BIT) {
+        size += VP8BitCost(bit, token & 0xffu);
+      } else {
+        size += VP8BitCost(bit, probas[token & 0x3fffu]);
+      }
+    }
+    p = next;
+  }
+  return size;
+}
+
+//------------------------------------------------------------------------------
+
+#else     // DISABLE_TOKEN_BUFFER
+
+void VP8TBufferInit(VP8TBuffer* const b, int page_size) {
+  (void)b;
+  (void)page_size;
+}
+void VP8TBufferClear(VP8TBuffer* const b) {
+  (void)b;
+}
+
+#endif    // !DISABLE_TOKEN_BUFFER
+