diff --git a/libavcodec/vb.c b/libavcodec/vb.c index 96387b6d1d..a1052ef95f 100644 --- a/libavcodec/vb.c +++ b/libavcodec/vb.c @@ -44,7 +44,7 @@ typedef struct VBDecContext { uint8_t *frame, *prev_frame; uint32_t pal[AVPALETTE_COUNT]; - const uint8_t *stream; + GetByteContext stream; } VBDecContext; static const uint16_t vb_patterns[64] = { @@ -62,8 +62,8 @@ static void vb_decode_palette(VBDecContext *c, int data_size) { int start, size, i; - start = bytestream_get_byte(&c->stream); - size = (bytestream_get_byte(&c->stream) - 1) & 0xFF; + start = bytestream2_get_byte(&c->stream); + size = (bytestream2_get_byte(&c->stream) - 1) & 0xFF; if(start + size > 255){ av_log(c->avctx, AV_LOG_ERROR, "Palette change runs beyond entry 256\n"); return; @@ -73,7 +73,7 @@ static void vb_decode_palette(VBDecContext *c, int data_size) return; } for(i = start; i <= start + size; i++) - c->pal[i] = bytestream_get_be24(&c->stream); + c->pal[i] = bytestream2_get_be24(&c->stream); } static inline int check_pixel(uint8_t *buf, uint8_t *start, uint8_t *end) @@ -86,10 +86,10 @@ static inline int check_line(uint8_t *buf, uint8_t *start, uint8_t *end) return buf >= start && (buf + 4) <= end; } -static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_size, int offset) +static int vb_decode_framedata(VBDecContext *c, int offset) { + GetByteContext g; uint8_t *prev, *cur; - const uint8_t* data_end = buf + data_size; int blk, blocks, t, blk2; int blocktypes = 0; int x, y, a, b; @@ -98,6 +98,8 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz uint8_t *pstart = c->prev_frame; uint8_t *pend = c->prev_frame + width*c->avctx->height; + g = c->stream; + prev = c->prev_frame + offset; cur = c->frame; @@ -105,11 +107,7 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz blk2 = 0; for(blk = 0; blk < blocks; blk++){ if(!(blk & 3)) { - if(buf >= data_end){ - av_log(c->avctx, AV_LOG_ERROR, "Data pointer out of bounds\n"); - return -1; - } - blocktypes = bytestream_get_byte(&buf); + blocktypes = bytestream2_get_byte(&g); } switch(blocktypes & 0xC0){ case 0x00: //skip @@ -120,15 +118,14 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz memset(cur + y*width, 0, 4); break; case 0x40: - t = bytestream_get_byte(&buf); + t = bytestream2_get_byte(&g); if(!t){ //raw block - if(buf + 16 > data_end){ + if (bytestream2_get_bytes_left(&g) < 16) { av_log(c->avctx, AV_LOG_ERROR, "Insufficient data\n"); return -1; } for(y = 0; y < 4; y++) - memcpy(cur + y*width, buf + y*4, 4); - buf += 16; + bytestream2_get_buffer(&g, cur + y * width, 4); }else{ // motion compensation x = ((t & 0xF)^8) - 8; y = ((t >> 4) ^8) - 8; @@ -141,22 +138,18 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz } break; case 0x80: // fill - t = bytestream_get_byte(&buf); + t = bytestream2_get_byte(&g); for(y = 0; y < 4; y++) memset(cur + y*width, t, 4); break; case 0xC0: // pattern fill - if(buf + 2 > data_end){ - av_log(c->avctx, AV_LOG_ERROR, "Insufficient data\n"); - return -1; - } - t = bytestream_get_byte(&buf); + t = bytestream2_get_byte(&g); pattype = t >> 6; pattern = vb_patterns[t & 0x3F]; switch(pattype){ case 0: - a = bytestream_get_byte(&buf); - b = bytestream_get_byte(&buf); + a = bytestream2_get_byte(&g); + b = bytestream2_get_byte(&g); for(y = 0; y < 4; y++) for(x = 0; x < 4; x++, pattern >>= 1) cur[x + y*width] = (pattern & 1) ? b : a; @@ -164,7 +157,7 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz case 1: pattern = ~pattern; case 2: - a = bytestream_get_byte(&buf); + a = bytestream2_get_byte(&g); for(y = 0; y < 4; y++) for(x = 0; x < 4; x++, pattern >>= 1) if(pattern & 1 && check_pixel(prev + x + y*width, pstart, pend)) @@ -193,16 +186,15 @@ static int vb_decode_framedata(VBDecContext *c, const uint8_t *buf, int data_siz static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { - const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; VBDecContext * const c = avctx->priv_data; uint8_t *outptr, *srcptr; int i, j; int flags; uint32_t size; - int rest = buf_size; int offset = 0; + bytestream2_init(&c->stream, avpkt->data, avpkt->size); + if(c->pic.data[0]) avctx->release_buffer(avctx, &c->pic); c->pic.reference = 1; @@ -211,34 +203,21 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac return -1; } - c->stream = buf; - flags = bytestream_get_le16(&c->stream); - rest -= 2; + flags = bytestream2_get_le16(&c->stream); if(flags & VB_HAS_GMC){ - i = (int16_t)bytestream_get_le16(&c->stream); - j = (int16_t)bytestream_get_le16(&c->stream); + i = (int16_t)bytestream2_get_le16(&c->stream); + j = (int16_t)bytestream2_get_le16(&c->stream); offset = i + j * avctx->width; - rest -= 4; } if(flags & VB_HAS_VIDEO){ - size = bytestream_get_le32(&c->stream); - if(size > rest){ - av_log(avctx, AV_LOG_ERROR, "Frame size is too big\n"); - return -1; - } - vb_decode_framedata(c, c->stream, size, offset); - c->stream += size - 4; - rest -= size; + size = bytestream2_get_le32(&c->stream); + vb_decode_framedata(c, offset); + bytestream2_skip(&c->stream, size - 4); } if(flags & VB_HAS_PALETTE){ - size = bytestream_get_le32(&c->stream); - if(size > rest){ - av_log(avctx, AV_LOG_ERROR, "Palette size is too big\n"); - return -1; - } + size = bytestream2_get_le32(&c->stream); vb_decode_palette(c, size); - rest -= size; } memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE); @@ -259,7 +238,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac *(AVFrame*)data = c->pic; /* always report that the buffer was completely consumed */ - return buf_size; + return avpkt->size; } static av_cold int decode_init(AVCodecContext *avctx)