From 0afcf97e1ece51d29bb791698b00cd1b7ba97dcf Mon Sep 17 00:00:00 2001 From: Alexandra Khirnova Date: Wed, 13 Mar 2013 13:54:27 +0100 Subject: [PATCH] vmdav: convert to bytestream2 Signed-off-by: Anton Khirnov --- libavcodec/vmdav.c | 152 ++++++++++++++++++--------------------------- 1 file changed, 59 insertions(+), 93 deletions(-) diff --git a/libavcodec/vmdav.c b/libavcodec/vmdav.c index 8c6c7d5da4..e6c75868e5 100644 --- a/libavcodec/vmdav.c +++ b/libavcodec/vmdav.c @@ -48,6 +48,7 @@ #include "libavutil/intreadwrite.h" #include "avcodec.h" #include "internal.h" +#include "bytestream.h" #define VMD_HEADER_SIZE 0x330 #define PALETTE_COUNT 256 @@ -77,8 +78,6 @@ typedef struct VmdVideoContext { static void lz_unpack(const unsigned char *src, int src_len, unsigned char *dest, int dest_len) { - const unsigned char *s; - unsigned int s_len; unsigned char *d; unsigned char *d_end; unsigned char queue[QUEUE_SIZE]; @@ -89,18 +88,17 @@ static void lz_unpack(const unsigned char *src, int src_len, unsigned int speclen; unsigned char tag; unsigned int i, j; + GetByteContext gb; - s = src; - s_len = src_len; + bytestream2_init(&gb, src, src_len); d = dest; d_end = d + dest_len; - dataleft = AV_RL32(s); - s += 4; s_len -= 4; + dataleft = bytestream2_get_le32(&gb); memset(queue, 0x20, QUEUE_SIZE); - if (s_len < 4) + if (bytestream2_get_bytes_left(&gb) < 4) return; - if (AV_RL32(s) == 0x56781234) { - s += 4; s_len -= 4; + if (bytestream2_peek_le32(&gb) == 0x56781234) { + bytestream2_get_le32(&gb); qpos = 0x111; speclen = 0xF + 3; } else { @@ -108,40 +106,32 @@ static void lz_unpack(const unsigned char *src, int src_len, speclen = 100; /* no speclen */ } - while (dataleft > 0 && s_len > 0) { - tag = *s++; s_len--; + while (dataleft > 0 && bytestream2_get_bytes_left(&gb) > 0) { + tag = bytestream2_get_byteu(&gb); if ((tag == 0xFF) && (dataleft > 8)) { - if (d + 8 > d_end || s_len < 8) + if (d + 8 > d_end || bytestream2_get_bytes_left(&gb) < 8) return; for (i = 0; i < 8; i++) { - queue[qpos++] = *d++ = *s++; + queue[qpos++] = *d++ = bytestream2_get_byteu(&gb); qpos &= QUEUE_MASK; } - s_len -= 8; dataleft -= 8; } else { for (i = 0; i < 8; i++) { if (dataleft == 0) break; if (tag & 0x01) { - if (d + 1 > d_end || s_len < 1) + if (d + 1 > d_end || bytestream2_get_bytes_left(&gb) < 1) return; - queue[qpos++] = *d++ = *s++; + queue[qpos++] = *d++ = bytestream2_get_byte(&gb); qpos &= QUEUE_MASK; dataleft--; - s_len--; } else { - if (s_len < 2) - return; - chainofs = *s++; - chainofs |= ((*s & 0xF0) << 4); - chainlen = (*s++ & 0x0F) + 3; - s_len -= 2; + chainofs = bytestream2_get_byte(&gb); + chainofs |= ((bytestream2_peek_byte(&gb) & 0xF0) << 4); + chainlen = (bytestream2_get_byte(&gb) & 0x0F) + 3; if (chainlen == speclen) { - if (s_len < 1) - return; - chainlen = *s++ + 0xF + 3; - s_len--; + chainlen = bytestream2_get_byte(&gb) + 0xF + 3; } if (d + chainlen > d_end) return; @@ -161,49 +151,44 @@ static void lz_unpack(const unsigned char *src, int src_len, static int rle_unpack(const unsigned char *src, unsigned char *dest, int src_count, int src_size, int dest_len) { - const unsigned char *ps; unsigned char *pd; int i, l; unsigned char *dest_end = dest + dest_len; + GetByteContext gb; - ps = src; + bytestream2_init(&gb, src, src_size); pd = dest; if (src_count & 1) { - if (src_size < 1) + if (bytestream2_get_bytes_left(&gb) < 1) return 0; - *pd++ = *ps++; - src_size--; + *pd++ = bytestream2_get_byteu(&gb); } src_count >>= 1; i = 0; do { - if (src_size < 1) + if (bytestream2_get_bytes_left(&gb) < 1) break; - l = *ps++; - src_size--; + l = bytestream2_get_byteu(&gb); if (l & 0x80) { l = (l & 0x7F) * 2; - if (pd + l > dest_end || src_size < l) - return ps - src; - memcpy(pd, ps, l); - ps += l; - src_size -= l; + if (pd + l > dest_end || bytestream2_get_bytes_left(&gb) < l) + return bytestream2_tell(&gb); + bytestream2_get_buffer(&gb, pd, l); pd += l; } else { - if (pd + i > dest_end || src_size < 2) - return ps - src; + if (pd + i > dest_end || bytestream2_get_bytes_left(&gb) < 2) + return bytestream2_tell(&gb); for (i = 0; i < l; i++) { - *pd++ = ps[0]; - *pd++ = ps[1]; + *pd++ = bytestream2_get_byteu(&gb); + *pd++ = bytestream2_get_byteu(&gb); } - ps += 2; - src_size -= 2; + bytestream2_skip(&gb, 2); } i += l; } while (i < src_count); - return ps - src; + return bytestream2_tell(&gb); } static void vmd_decode(VmdVideoContext *s, AVFrame *frame) @@ -212,11 +197,8 @@ static void vmd_decode(VmdVideoContext *s, AVFrame *frame) unsigned int *palette32; unsigned char r, g, b; - /* point to the start of the encoded data */ - const unsigned char *p = s->buf + 16; + GetByteContext gb; - const unsigned char *pb; - unsigned int pb_size; unsigned char meth; unsigned char *dp; /* pointer to current frame */ unsigned char *pp; /* pointer to previous frame */ @@ -261,30 +243,31 @@ static void vmd_decode(VmdVideoContext *s, AVFrame *frame) } /* check if there is a new palette */ + bytestream2_init(&gb, s->buf + 16, s->size - 16); if (s->buf[15] & 0x02) { - p += 2; + bytestream2_skip(&gb, 2); palette32 = (unsigned int *)s->palette; - for (i = 0; i < PALETTE_COUNT; i++) { - r = *p++ * 4; - g = *p++ * 4; - b = *p++ * 4; - palette32[i] = (r << 16) | (g << 8) | (b); + if (bytestream2_get_bytes_left(&gb) >= PALETTE_COUNT * 3) { + for (i = 0; i < PALETTE_COUNT; i++) { + r = bytestream2_get_byteu(&gb) * 4; + g = bytestream2_get_byteu(&gb) * 4; + b = bytestream2_get_byteu(&gb) * 4; + palette32[i] = (r << 16) | (g << 8) | (b); + } } s->size -= (256 * 3 + 2); } if (s->size > 0) { /* originally UnpackFrame in VAG's code */ - pb = p; - pb_size = s->buf + s->size - pb; - if (pb_size < 1) + bytestream2_init(&gb, gb.buffer, s->buf + s->size - gb.buffer); + if (bytestream2_get_bytes_left(&gb) < 1) return; - meth = *pb++; pb_size--; + meth = bytestream2_get_byteu(&gb); if (meth & 0x80) { - lz_unpack(pb, pb_size, + lz_unpack(gb.buffer, bytestream2_get_bytes_left(&gb), s->unpack_buffer, s->unpack_buffer_size); meth &= 0x7F; - pb = s->unpack_buffer; - pb_size = s->unpack_buffer_size; + bytestream2_init(&gb, s->unpack_buffer, s->unpack_buffer_size); } dp = &frame->data[0][frame_y * frame->linesize[0] + frame_x]; @@ -294,17 +277,12 @@ static void vmd_decode(VmdVideoContext *s, AVFrame *frame) for (i = 0; i < frame_height; i++) { ofs = 0; do { - if (pb_size < 1) - return; - len = *pb++; - pb_size--; + len = bytestream2_get_byte(&gb); if (len & 0x80) { len = (len & 0x7F) + 1; - if (ofs + len > frame_width || pb_size < len) + if (ofs + len > frame_width || bytestream2_get_bytes_left(&gb) < len) return; - memcpy(&dp[ofs], pb, len); - pb += len; - pb_size -= len; + bytestream2_get_buffer(&gb, &dp[ofs], len); ofs += len; } else { /* interframe pixel copy */ @@ -326,11 +304,7 @@ static void vmd_decode(VmdVideoContext *s, AVFrame *frame) case 2: for (i = 0; i < frame_height; i++) { - if (pb_size < frame_width) - return; - memcpy(dp, pb, frame_width); - pb += frame_width; - pb_size -= frame_width; + bytestream2_get_buffer(&gb, dp, frame_width); dp += frame->linesize[0]; pp += s->prev_frame.linesize[0]; } @@ -340,24 +314,16 @@ static void vmd_decode(VmdVideoContext *s, AVFrame *frame) for (i = 0; i < frame_height; i++) { ofs = 0; do { - if (pb_size < 1) - return; - len = *pb++; - pb_size--; + len = bytestream2_get_byte(&gb); if (len & 0x80) { len = (len & 0x7F) + 1; - if (pb_size < 1) - return; - if (*pb++ == 0xFF) - len = rle_unpack(pb, &dp[ofs], len, pb_size, frame_width - ofs); - else { - if (pb_size < len) - return; - memcpy(&dp[ofs], pb, len); - } - pb += len; - pb_size -= 1 + len; - ofs += len; + if (bytestream2_get_byte(&gb) == 0xFF) + len = rle_unpack(gb.buffer, &dp[ofs], + len, bytestream2_get_bytes_left(&gb), + frame_width - ofs); + else + bytestream2_get_buffer(&gb, &dp[ofs], len); + bytestream2_skip(&gb, len); } else { /* interframe pixel copy */ if (ofs + len + 1 > frame_width || !s->prev_frame.data[0])