From ec036557d816e4b451b7c4a12321d74cb46eb2b1 Mon Sep 17 00:00:00 2001 From: Alexandra Hájková Date: Sat, 9 Apr 2016 20:36:57 +0200 Subject: escape124: Convert to the new bitstream reader Signed-off-by: Anton Khirnov --- libavcodec/escape124.c | 85 ++++++++++++++++++++++++-------------------------- 1 file changed, 41 insertions(+), 44 deletions(-) diff --git a/libavcodec/escape124.c b/libavcodec/escape124.c index 6d1b487d1b..879f00a73c 100644 --- a/libavcodec/escape124.c +++ b/libavcodec/escape124.c @@ -21,7 +21,7 @@ #define BITSTREAM_READER_LE #include "avcodec.h" -#include "get_bits.h" +#include "bitstream.h" #include "internal.h" typedef union MacroBlock { @@ -48,8 +48,9 @@ typedef struct Escape124Context { CodeBook codebooks[3]; } Escape124Context; -static int can_safely_read(GetBitContext* gb, int bits) { - return get_bits_left(gb) >= bits; +static int can_safely_read(BitstreamContext *bc, int bits) +{ + return bitstream_bits_left(bc) >= bits; } /** @@ -86,13 +87,13 @@ static av_cold int escape124_decode_close(AVCodecContext *avctx) return 0; } -static CodeBook unpack_codebook(GetBitContext* gb, unsigned depth, +static CodeBook unpack_codebook(BitstreamContext *bc, unsigned depth, unsigned size) { unsigned i, j; CodeBook cb = { 0 }; - if (!can_safely_read(gb, size * 34)) + if (!can_safely_read(bc, size * 34)) return cb; if (size >= INT_MAX / sizeof(MacroBlock)) @@ -104,9 +105,9 @@ static CodeBook unpack_codebook(GetBitContext* gb, unsigned depth, cb.depth = depth; cb.size = size; for (i = 0; i < size; i++) { - unsigned mask_bits = get_bits(gb, 4); - unsigned color0 = get_bits(gb, 15); - unsigned color1 = get_bits(gb, 15); + unsigned mask_bits = bitstream_read(bc, 4); + unsigned color0 = bitstream_read(bc, 15); + unsigned color1 = bitstream_read(bc, 15); for (j = 0; j < 4; j++) { if (mask_bits & (1 << j)) @@ -118,47 +119,43 @@ static CodeBook unpack_codebook(GetBitContext* gb, unsigned depth, return cb; } -static unsigned decode_skip_count(GetBitContext* gb) +static unsigned decode_skip_count(BitstreamContext *bc) { unsigned value; // This function reads a maximum of 23 bits, // which is within the padding space - if (!can_safely_read(gb, 1)) + if (!can_safely_read(bc, 1)) return -1; - value = get_bits1(gb); + value = bitstream_read_bit(bc); if (!value) return value; - value += get_bits(gb, 3); + value += bitstream_read(bc, 3); if (value != (1 + ((1 << 3) - 1))) return value; - value += get_bits(gb, 7); + value += bitstream_read(bc, 7); if (value != (1 + ((1 << 3) - 1)) + ((1 << 7) - 1)) return value; - return value + get_bits(gb, 12); + return value + bitstream_read(bc, 12); } -static MacroBlock decode_macroblock(Escape124Context* s, GetBitContext* gb, - int* codebook_index, int superblock_index) +static MacroBlock decode_macroblock(Escape124Context *s, BitstreamContext *bc, + int *codebook_index, int superblock_index) { // This function reads a maximum of 22 bits; the callers // guard this function appropriately unsigned block_index, depth; - int value = get_bits1(gb); + int value = bitstream_read_bit(bc); if (value) { static const char transitions[3][2] = { {2, 1}, {0, 2}, {1, 0} }; - value = get_bits1(gb); + value = bitstream_read_bit(bc); *codebook_index = transitions[*codebook_index][value]; } depth = s->codebooks[*codebook_index].depth; - - // depth = 0 means that this shouldn't read any bits; - // in theory, this is the same as get_bits(gb, 0), but - // that doesn't actually work. - block_index = get_bitsz(gb, depth); + block_index = bitstream_read(bc, depth); if (*codebook_index == 1) { block_index += superblock_index << s->codebooks[1].depth; @@ -208,7 +205,7 @@ static int escape124_decode_frame(AVCodecContext *avctx, Escape124Context *s = avctx->priv_data; AVFrame *frame = data; - GetBitContext gb; + BitstreamContext bc; unsigned frame_flags, frame_size; unsigned i; @@ -220,15 +217,15 @@ static int escape124_decode_frame(AVCodecContext *avctx, unsigned old_stride, new_stride; int ret; - init_get_bits(&gb, buf, buf_size * 8); + bitstream_init(&bc, buf, buf_size * 8); // This call also guards the potential depth reads for the // codebook unpacking. - if (!can_safely_read(&gb, 64)) + if (!can_safely_read(&bc, 64)) return -1; - frame_flags = get_bits_long(&gb, 32); - frame_size = get_bits_long(&gb, 32); + frame_flags = bitstream_read(&bc, 32); + frame_size = bitstream_read(&bc, 32); // Leave last frame unchanged // FIXME: Is this necessary? I haven't seen it in any real samples @@ -251,10 +248,10 @@ static int escape124_decode_frame(AVCodecContext *avctx, if (i == 2) { // This codebook can be cut off at places other than // powers of 2, leaving some of the entries undefined. - cb_size = get_bits_long(&gb, 20); + cb_size = bitstream_read(&bc, 20); cb_depth = av_log2(cb_size - 1) + 1; } else { - cb_depth = get_bits(&gb, 4); + cb_depth = bitstream_read(&bc, 4); if (i == 0) { // This is the most basic codebook: pow(2,depth) entries // for a depth-length key @@ -267,7 +264,7 @@ static int escape124_decode_frame(AVCodecContext *avctx, } } av_free(s->codebooks[i].blocks); - s->codebooks[i] = unpack_codebook(&gb, cb_depth, cb_size); + s->codebooks[i] = unpack_codebook(&bc, cb_depth, cb_size); if (!s->codebooks[i].blocks) return -1; } @@ -292,7 +289,7 @@ static int escape124_decode_frame(AVCodecContext *avctx, if (skip == -1) { // Note that this call will make us skip the rest of the blocks // if the frame prematurely ends - skip = decode_skip_count(&gb); + skip = decode_skip_count(&bc); } if (skip) { @@ -302,10 +299,10 @@ static int escape124_decode_frame(AVCodecContext *avctx, copy_superblock(sb.pixels, 8, old_frame_data, old_stride); - while (can_safely_read(&gb, 1) && !get_bits1(&gb)) { + while (can_safely_read(&bc, 1) && !bitstream_read_bit(&bc)) { unsigned mask; - mb = decode_macroblock(s, &gb, &cb_index, superblock_index); - mask = get_bits(&gb, 16); + mb = decode_macroblock(s, &bc, &cb_index, superblock_index); + mask = bitstream_read(&bc, 16); multi_mask |= mask; for (i = 0; i < 16; i++) { if (mask & mask_matrix[i]) { @@ -314,29 +311,29 @@ static int escape124_decode_frame(AVCodecContext *avctx, } } - if (can_safely_read(&gb, 1) && !get_bits1(&gb)) { - unsigned inv_mask = get_bits(&gb, 4); + if (can_safely_read(&bc, 1) && !bitstream_read_bit(&bc)) { + unsigned inv_mask = bitstream_read(&bc, 4); for (i = 0; i < 4; i++) { if (inv_mask & (1 << i)) { multi_mask ^= 0xF << i*4; } else { - multi_mask ^= get_bits(&gb, 4) << i*4; + multi_mask ^= bitstream_read(&bc, 4) << i * 4; } } for (i = 0; i < 16; i++) { if (multi_mask & mask_matrix[i]) { - if (!can_safely_read(&gb, 1)) + if (!can_safely_read(&bc, 1)) break; - mb = decode_macroblock(s, &gb, &cb_index, + mb = decode_macroblock(s, &bc, &cb_index, superblock_index); insert_mb_into_sb(&sb, mb, i); } } } else if (frame_flags & (1 << 16)) { - while (can_safely_read(&gb, 1) && !get_bits1(&gb)) { - mb = decode_macroblock(s, &gb, &cb_index, superblock_index); - insert_mb_into_sb(&sb, mb, get_bits(&gb, 4)); + while (can_safely_read(&bc, 1) && !bitstream_read_bit(&bc)) { + mb = decode_macroblock(s, &bc, &cb_index, superblock_index); + insert_mb_into_sb(&sb, mb, bitstream_read(&bc, 4)); } } @@ -358,7 +355,7 @@ static int escape124_decode_frame(AVCodecContext *avctx, av_log(NULL, AV_LOG_DEBUG, "Escape sizes: %i, %i, %i\n", - frame_size, buf_size, get_bits_count(&gb) / 8); + frame_size, buf_size, bitstream_tell(&bc) / 8); av_frame_unref(s->frame); if ((ret = av_frame_ref(s->frame, frame)) < 0) -- cgit v1.2.3