diff options
| -rw-r--r-- | Changelog | 1 | ||||
| -rw-r--r-- | libavcodec/sgidec.c | 56 |
2 files changed, 51 insertions, 6 deletions
@@ -12,6 +12,7 @@ version <next>: - Improvments to the XBM decoder - QTKit input device - improvments to OpenEXR image decoder +- support decoding 16-bit RLE SGI images version 2.2: diff --git a/libavcodec/sgidec.c b/libavcodec/sgidec.c index b29a5dd..6f51ec3 100644 --- a/libavcodec/sgidec.c +++ b/libavcodec/sgidec.c @@ -44,8 +44,8 @@ typedef struct SgiState { * @param pixelstride pixel stride of input buffer * @return size of output in bytes, else return error code. */ -static int expand_rle_row(SgiState *s, uint8_t *out_buf, - int len, int pixelstride) +static int expand_rle_row8(SgiState *s, uint8_t *out_buf, + int len, int pixelstride) { unsigned char pixel, count; unsigned char *orig = out_buf; @@ -82,6 +82,46 @@ static int expand_rle_row(SgiState *s, uint8_t *out_buf, return (out_buf - orig) / pixelstride; } +static int expand_rle_row16(SgiState *s, uint16_t *out_buf, + int len, int pixelstride) +{ + unsigned short pixel; + unsigned char count; + unsigned short *orig = out_buf; + uint16_t *out_end = out_buf + len; + + while (out_buf < out_end) { + if (bytestream2_get_bytes_left(&s->g) < 2) + return AVERROR_INVALIDDATA; + pixel = bytestream2_get_be16u(&s->g); + if (!(count = (pixel & 0x7f))) + break; + + /* Check for buffer overflow. */ + if (pixelstride * (count - 1) >= len) { + av_log(s->avctx, AV_LOG_ERROR, "Invalid pixel count.\n"); + return AVERROR_INVALIDDATA; + } + + if (pixel & 0x80) { + while (count--) { + pixel = bytestream2_get_ne16(&s->g); + AV_WN16A(out_buf, pixel); + out_buf += pixelstride; + } + } else { + pixel = bytestream2_get_ne16(&s->g); + + while (count--) { + AV_WN16A(out_buf, pixel); + out_buf += pixelstride; + } + } + } + return (out_buf - orig) / pixelstride; +} + + /** * Read a run length encoded SGI image. * @param out_buf output buffer @@ -95,6 +135,7 @@ static int read_rle_sgi(uint8_t *out_buf, SgiState *s) GetByteContext g_table = s->g; unsigned int y, z; unsigned int start_offset; + int linesize, ret; /* size of RLE offset and length tables */ if (len * 2 > bytestream2_get_bytes_left(&s->g)) { @@ -104,13 +145,16 @@ static int read_rle_sgi(uint8_t *out_buf, SgiState *s) for (z = 0; z < s->depth; z++) { dest_row = out_buf; for (y = 0; y < s->height; y++) { + linesize = s->width * s->depth * s->bytes_per_channel; dest_row -= s->linesize; start_offset = bytestream2_get_be32(&g_table); bytestream2_seek(&s->g, start_offset, SEEK_SET); - if (expand_rle_row(s, dest_row + z, s->width * s->depth, - s->depth) != s->width) { + if (s->bytes_per_channel == 1) + ret = expand_rle_row8(s, dest_row + z, linesize, s->depth); + else + ret = expand_rle_row16(s, (uint16_t *)dest_row + z, linesize, s->depth); + if (ret != s->width) return AVERROR_INVALIDDATA; - } } } return 0; @@ -184,7 +228,7 @@ static int decode_frame(AVCodecContext *avctx, s->height = bytestream2_get_be16u(&s->g); s->depth = bytestream2_get_be16u(&s->g); - if (s->bytes_per_channel != 1 && (s->bytes_per_channel != 2 || rle)) { + if (s->bytes_per_channel != 1 && s->bytes_per_channel != 2) { av_log(avctx, AV_LOG_ERROR, "wrong channel number\n"); return AVERROR_INVALIDDATA; } |
