The earlier code only used the counts from the last slice. The two FATE tests using slices show compression improvements due to this.
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| @@ -395,20 +395,20 @@ static int encode_table(AVCodecContext *avctx, · 394 unmodified lines | |||
| 395 | PutBitContext *pb, HuffEntry *he, int plane) | 395 | PutBitContext *pb, HuffEntry *he, int plane) |
| 396 | { | 396 | { |
| 397 | MagicYUVContext *s = avctx->priv_data; | 397 | MagicYUVContext *s = avctx->priv_data; |
| 398 | PTable counts[256] = { {0} }; | 398 | PTable counts[256]; |
| 399 | uint16_t codes_counts[33] = { 0 }; | 399 | uint16_t codes_counts[33] = { 0 }; |
| 400 | 400 | ||
| 401 | for (size_t i = 0; i < FF_ARRAY_ELEMS(counts); i++) { | ||
| 402 | counts[i].prob = 1; | ||
| 403 | counts[i].value = i; | ||
| 404 | } | ||
| 405 | |||
| 401 | for (int n = 0; n < s->nb_slices; n++) { | 406 | for (int n = 0; n < s->nb_slices; n++) { |
| 402 | Slice *sl = &s->slices[n * s->planes + plane]; | 407 | Slice *sl = &s->slices[n * s->planes + plane]; |
| 403 | PTable *slice_counts = sl->counts; | 408 | PTable *slice_counts = sl->counts; |
| 404 | 409 | ||
| 405 | for (int i = 0; i < 256; i++) | 410 | for (int i = 0; i < 256; i++) |
| 406 | counts[i].prob = slice_counts[i].prob; | 411 | counts[i].prob += slice_counts[i].prob; |
| 407 | } | ||
| 408 | |||
| 409 | for (int i = 0; i < 256; i++) { | ||
| 410 | counts[i].prob++; | ||
| 411 | counts[i].value = i; | ||
| 412 | } | 412 | } |
| 413 | 413 | ||
| 414 | magy_huffman_compute_bits(counts, he, codes_counts, 256, 12); | 414 | magy_huffman_compute_bits(counts, he, codes_counts, 256, 12); |