* Escape 124 Video Decoder
* Copyright (C) 2008 Eli Friedman (eli.friedman@gmail.com)
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
-#define ALT_BITSTREAM_READER_LE
-#include "bitstream.h"
+#define BITSTREAM_READER_LE
+#include "get_bits.h"
typedef union MacroBlock {
uint16_t pixels[4];
typedef struct CodeBook {
unsigned depth;
unsigned size;
- MacroBlock blocks[0];
+ MacroBlock* blocks;
} CodeBook;
typedef struct Escape124Context {
unsigned num_superblocks;
- CodeBook* codebooks[3];
+ CodeBook codebooks[3];
} Escape124Context;
static int can_safely_read(GetBitContext* gb, int bits) {
Escape124Context *s = avctx->priv_data;
for (i = 0; i < 3; i++)
- av_free(s->codebooks[i]);
+ av_free(s->codebooks[i].blocks);
if (s->frame.data[0])
avctx->release_buffer(avctx, &s->frame);
return 0;
}
-static CodeBook* unpack_codebook(GetBitContext* gb, unsigned depth,
+static CodeBook unpack_codebook(GetBitContext* gb, unsigned depth,
unsigned size)
{
unsigned i, j;
- CodeBook* cb;
+ CodeBook cb = { 0 };
if (!can_safely_read(gb, size * 34))
- return NULL;
+ return cb;
- if (size >= (INT_MAX - sizeof(CodeBook)) / sizeof(MacroBlock))
- return NULL;
- cb = av_malloc(size * sizeof(MacroBlock) + sizeof(CodeBook));
- if (!cb)
- return NULL;
+ if (size >= INT_MAX / sizeof(MacroBlock))
+ return cb;
+ cb.blocks = av_malloc(size ? size * sizeof(MacroBlock) : 1);
+ if (!cb.blocks)
+ return cb;
- cb->depth = depth;
- cb->size = size;
+ 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);
for (j = 0; j < 4; j++) {
if (mask_bits & (1 << j))
- cb->blocks[i].pixels[j] = color1;
+ cb.blocks[i].pixels[j] = color1;
else
- cb->blocks[i].pixels[j] = color0;
+ cb.blocks[i].pixels[j] = color0;
}
}
return cb;
*codebook_index = transitions[*codebook_index][get_bits1(gb)];
}
- depth = s->codebooks[*codebook_index]->depth;
+ 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
block_index = depth ? get_bits(gb, depth) : 0;
if (*codebook_index == 1) {
- block_index += superblock_index << s->codebooks[1]->depth;
+ block_index += superblock_index << s->codebooks[1].depth;
}
// This condition can occur with invalid bitstreams and
// *codebook_index == 2
- if (block_index >= s->codebooks[*codebook_index]->size)
+ if (block_index >= s->codebooks[*codebook_index].size)
return (MacroBlock) { { 0 } };
- return s->codebooks[*codebook_index]->blocks[block_index];
+ return s->codebooks[*codebook_index].blocks[block_index];
}
static void insert_mb_into_sb(SuperBlock* sb, MacroBlock mb, unsigned index) {
0x100, 0x200, 0x1000, 0x2000,
0x400, 0x800, 0x4000, 0x8000};
-/**
- * Decode a single frame
- * @param avctx decoder context
- * @param data decoded frame
- * @param data_size size of the decoded frame
- * @param buf input buffer
- * @param buf_size input buffer size
- * @return 0 success, -1 on error
- */
static int escape124_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
- const uint8_t *buf, int buf_size)
+ AVPacket *avpkt)
{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
Escape124Context *s = avctx->priv_data;
GetBitContext gb;
cb_size = s->num_superblocks << cb_depth;
}
}
- av_free(s->codebooks[i]);
+ av_free(s->codebooks[i].blocks);
s->codebooks[i] = unpack_codebook(&gb, cb_depth, cb_size);
- if (!s->codebooks[i])
+ if (!s->codebooks[i].blocks)
return -1;
}
}
}
-AVCodec escape124_decoder = {
- "escape124",
- CODEC_TYPE_VIDEO,
- CODEC_ID_ESCAPE124,
- sizeof(Escape124Context),
- escape124_decode_init,
- NULL,
- escape124_decode_close,
- escape124_decode_frame,
- CODEC_CAP_DR1,
+AVCodec ff_escape124_decoder = {
+ .name = "escape124",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = CODEC_ID_ESCAPE124,
+ .priv_data_size = sizeof(Escape124Context),
+ .init = escape124_decode_init,
+ .close = escape124_decode_close,
+ .decode = escape124_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Escape 124"),
};
-
projects / ffmpeg / blobdiff