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author | Kostya Shishkov <kostya.shishkov@gmail.com> | 2011-02-04 23:41:07 +0100 |
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committer | Michael Niedermayer <michaelni@gmx.at> | 2011-02-09 03:31:18 +0100 |
commit | abb5f2b7bfeab08568bdeb2fa3564c7c3851372e (patch) | |
tree | fd134e629029ef2b3ef6b94b621641daf8ccecb1 /libavcodec/xxan.c | |
parent | 14d735bd4f7c1dda547d4a4bd3de31536ef11a2a (diff) | |
download | ffmpeg-streaming-abb5f2b7bfeab08568bdeb2fa3564c7c3851372e.zip ffmpeg-streaming-abb5f2b7bfeab08568bdeb2fa3564c7c3851372e.tar.gz |
Xan4 decoder
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
(cherry picked from commit 44ddfd47d671d2587903d94c8b565f68f45bd4bc)
Diffstat (limited to 'libavcodec/xxan.c')
-rw-r--r-- | libavcodec/xxan.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/libavcodec/xxan.c b/libavcodec/xxan.c new file mode 100644 index 0000000..10ec53f --- /dev/null +++ b/libavcodec/xxan.c @@ -0,0 +1,429 @@ +/* + * Wing Commander/Xan Video Decoder + * Copyright (C) 2011 Konstantin Shishkov + * based on work by Mike Melanson + * + * This file is part of FFmpeg. + * + * FFmpeg 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, + * 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 + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "avcodec.h" +#include "libavutil/intreadwrite.h" +#include "bytestream.h" +#define ALT_BITSTREAM_READER_LE +#include "get_bits.h" +// for av_memcpy_backptr +#include "libavutil/lzo.h" + +typedef struct XanContext { + AVCodecContext *avctx; + AVFrame pic; + + uint8_t *y_buffer; + uint8_t *scratch_buffer; + int buffer_size; +} XanContext; + +static av_cold int xan_decode_init(AVCodecContext *avctx) +{ + XanContext *s = avctx->priv_data; + + s->avctx = avctx; + + avctx->pix_fmt = PIX_FMT_YUV420P; + + s->buffer_size = avctx->width * avctx->height; + s->y_buffer = av_malloc(s->buffer_size); + if (!s->y_buffer) + return AVERROR(ENOMEM); + s->scratch_buffer = av_malloc(s->buffer_size + 130); + if (!s->scratch_buffer) { + av_freep(&s->y_buffer); + return AVERROR(ENOMEM); + } + + return 0; +} + +static int xan_unpack_luma(const uint8_t *src, const int src_size, + uint8_t *dst, const int dst_size) +{ + int tree_size, eof; + const uint8_t *tree; + int bits, mask; + int tree_root, node; + const uint8_t *dst_end = dst + dst_size; + const uint8_t *src_end = src + src_size; + + tree_size = *src++; + eof = *src++; + tree = src - eof * 2 - 2; + tree_root = eof + tree_size; + src += tree_size * 2; + + node = tree_root; + bits = *src++; + mask = 0x80; + for (;;) { + int bit = !!(bits & mask); + mask >>= 1; + node = tree[node*2 + bit]; + if (node == eof) + break; + if (node < eof) { + *dst++ = node; + if (dst > dst_end) + break; + node = tree_root; + } + if (!mask) { + bits = *src++; + if (src > src_end) + break; + mask = 0x80; + } + } + return dst != dst_end; +} + +/* almost the same as in xan_wc3 decoder */ +static int xan_unpack(uint8_t *dest, const int dest_len, + const uint8_t *src, const int src_len) +{ + uint8_t opcode; + int size; + uint8_t *orig_dest = dest; + const uint8_t *src_end = src + src_len; + const uint8_t *dest_end = dest + dest_len; + + while (dest < dest_end) { + opcode = *src++; + + if (opcode < 0xe0) { + int size2, back; + if ((opcode & 0x80) == 0) { + size = opcode & 3; + back = ((opcode & 0x60) << 3) + *src++ + 1; + size2 = ((opcode & 0x1c) >> 2) + 3; + } else if ((opcode & 0x40) == 0) { + size = *src >> 6; + back = (bytestream_get_be16(&src) & 0x3fff) + 1; + size2 = (opcode & 0x3f) + 4; + } else { + size = opcode & 3; + back = ((opcode & 0x10) << 12) + bytestream_get_be16(&src) + 1; + size2 = ((opcode & 0x0c) << 6) + *src++ + 5; + if (size + size2 > dest_end - dest) + break; + } + if (src + size > src_end || dest + size + size2 > dest_end) + return -1; + bytestream_get_buffer(&src, dest, size); + dest += size; + av_memcpy_backptr(dest, back, size2); + dest += size2; + } else { + int finish = opcode >= 0xfc; + + size = finish ? opcode & 3 : ((opcode & 0x1f) << 2) + 4; + if (src + size > src_end || dest + size > dest_end) + return -1; + bytestream_get_buffer(&src, dest, size); + dest += size; + if (finish) + break; + } + } + return dest - orig_dest; +} + +static int xan_decode_chroma(AVCodecContext *avctx, AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + XanContext *s = avctx->priv_data; + uint8_t *U, *V; + unsigned chroma_off; + int val, uval, vval; + int i, j; + const uint8_t *src, *src_end; + const uint8_t *table; + int mode, offset, dec_size; + + chroma_off = AV_RL32(buf + 4); + if (!chroma_off) + return 0; + if (chroma_off + 10 >= avpkt->size) { + av_log(avctx, AV_LOG_ERROR, "Invalid chroma block position\n"); + return -1; + } + src = avpkt->data + 4 + chroma_off; + table = src + 2; + mode = bytestream_get_le16(&src); + offset = bytestream_get_le16(&src) * 2; + + if (src - avpkt->data >= avpkt->size - offset) { + av_log(avctx, AV_LOG_ERROR, "Invalid chroma block offset\n"); + return -1; + } + + memset(s->scratch_buffer, 0, s->buffer_size); + dec_size = xan_unpack(s->scratch_buffer, s->buffer_size, src + offset, + avpkt->size - offset - (src - avpkt->data)); + if (dec_size < 0) { + av_log(avctx, AV_LOG_ERROR, "Chroma unpacking failed\n"); + return -1; + } + + U = s->pic.data[1]; + V = s->pic.data[2]; + src = s->scratch_buffer; + src_end = src + dec_size; + if (mode) { + for (j = 0; j < avctx->height >> 1; j++) { + for (i = 0; i < avctx->width >> 1; i++) { + val = *src++; + if (val) { + val = AV_RL16(table + (val << 1)); + uval = (val >> 3) & 0xF8; + vval = (val >> 8) & 0xF8; + U[i] = uval | (uval >> 5); + V[i] = vval | (vval >> 5); + } + if (src == src_end) + return 0; + } + U += s->pic.linesize[1]; + V += s->pic.linesize[2]; + } + } else { + uint8_t *U2 = U + s->pic.linesize[1]; + uint8_t *V2 = V + s->pic.linesize[2]; + + for (j = 0; j < avctx->height >> 2; j++) { + for (i = 0; i < avctx->width >> 1; i += 2) { + val = *src++; + if (val) { + val = AV_RL16(table + (val << 1)); + uval = (val >> 3) & 0xF8; + vval = (val >> 8) & 0xF8; + U[i] = U[i+1] = U2[i] = U2[i+1] = uval | (uval >> 5); + V[i] = V[i+1] = V2[i] = V2[i+1] = vval | (vval >> 5); + } + } + U += s->pic.linesize[1] * 2; + V += s->pic.linesize[2] * 2; + U2 += s->pic.linesize[1] * 2; + V2 += s->pic.linesize[2] * 2; + } + } + + return 0; +} + +static int xan_decode_frame_type0(AVCodecContext *avctx, AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + XanContext *s = avctx->priv_data; + uint8_t *ybuf, *prev_buf, *src = s->scratch_buffer; + unsigned chroma_off, corr_off; + int cur, last, size; + int i, j; + int ret; + + corr_off = AV_RL32(buf + 8); + chroma_off = AV_RL32(buf + 4); + + if ((ret = xan_decode_chroma(avctx, avpkt)) != 0) + return ret; + + size = avpkt->size - 4; + if (corr_off >= avpkt->size) { + av_log(avctx, AV_LOG_WARNING, "Ignoring invalid correction block position\n"); + corr_off = 0; + } + if (corr_off) + size = corr_off; + if (chroma_off) + size = FFMIN(size, chroma_off); + ret = xan_unpack_luma(buf + 12, size, src, s->buffer_size >> 1); + if (ret) { + av_log(avctx, AV_LOG_ERROR, "Luma decoding failed\n"); + return ret; + } + + ybuf = s->y_buffer; + last = *src++; + ybuf[0] = last << 1; + for (j = 1; j < avctx->width - 1; j += 2) { + cur = (last + *src++) & 0x1F; + ybuf[j] = last + cur; + ybuf[j+1] = cur << 1; + last = cur; + } + ybuf[j] = last << 1; + prev_buf = ybuf; + ybuf += avctx->width; + + for (i = 1; i < avctx->height; i++) { + last = ((prev_buf[0] >> 1) + *src++) & 0x1F; + ybuf[0] = last << 1; + for (j = 1; j < avctx->width - 1; j += 2) { + cur = ((prev_buf[j + 1] >> 1) + *src++) & 0x1F; + ybuf[j] = last + cur; + ybuf[j+1] = cur << 1; + last = cur; + } + ybuf[j] = last << 1; + prev_buf = ybuf; + ybuf += avctx->width; + } + + if (corr_off) { + int corr_end, dec_size; + + corr_end = avpkt->size; + if (chroma_off > corr_off) + corr_end = chroma_off; + dec_size = xan_unpack(s->scratch_buffer, s->buffer_size, + avpkt->data + 8 + corr_off, + corr_end - corr_off); + if (dec_size < 0) + dec_size = 0; + for (i = 0; i < dec_size; i++) + s->y_buffer[i*2+1] = (s->y_buffer[i*2+1] + (s->scratch_buffer[i] << 1)) & 0x3F; + } + + src = s->y_buffer; + ybuf = s->pic.data[0]; + for (j = 0; j < avctx->height; j++) { + for (i = 0; i < avctx->width; i++) + ybuf[i] = (src[i] << 2) | (src[i] >> 3); + src += avctx->width; + ybuf += s->pic.linesize[0]; + } + + return 0; +} + +static int xan_decode_frame_type1(AVCodecContext *avctx, AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + XanContext *s = avctx->priv_data; + uint8_t *ybuf, *src = s->scratch_buffer; + int cur, last; + int i, j; + int ret; + + if ((ret = xan_decode_chroma(avctx, avpkt)) != 0) + return ret; + + ret = xan_unpack_luma(buf + 16, avpkt->size - 16, src, + s->buffer_size >> 1); + if (ret) { + av_log(avctx, AV_LOG_ERROR, "Luma decoding failed\n"); + return ret; + } + + ybuf = s->y_buffer; + for (i = 0; i < avctx->height; i++) { + last = (ybuf[0] + (*src++ << 1)) & 0x3F; + ybuf[0] = last; + for (j = 1; j < avctx->width - 1; j += 2) { + cur = (ybuf[j + 1] + (*src++ << 1)) & 0x3F; + ybuf[j] = (last + cur) >> 1; + ybuf[j+1] = cur; + last = cur; + } + ybuf[j] = last; + ybuf += avctx->width; + } + + src = s->y_buffer; + ybuf = s->pic.data[0]; + for (j = 0; j < avctx->height; j++) { + for (i = 0; i < avctx->width; i++) + ybuf[i] = (src[i] << 2) | (src[i] >> 3); + src += avctx->width; + ybuf += s->pic.linesize[0]; + } + + return 0; +} + +static int xan_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + AVPacket *avpkt) +{ + XanContext *s = avctx->priv_data; + int ftype; + int ret; + + s->pic.reference = 1; + s->pic.buffer_hints = FF_BUFFER_HINTS_VALID | + FF_BUFFER_HINTS_PRESERVE | + FF_BUFFER_HINTS_REUSABLE; + if ((ret = avctx->reget_buffer(avctx, &s->pic))) { + av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); + return ret; + } + + ftype = AV_RL32(avpkt->data); + switch (ftype) { + case 0: + ret = xan_decode_frame_type0(avctx, avpkt); + break; + case 1: + ret = xan_decode_frame_type1(avctx, avpkt); + break; + default: + av_log(avctx, AV_LOG_ERROR, "Unknown frame type %d\n", ftype); + return -1; + } + if (ret) + return ret; + + *data_size = sizeof(AVFrame); + *(AVFrame*)data = s->pic; + + return avpkt->size; +} + +static av_cold int xan_decode_end(AVCodecContext *avctx) +{ + XanContext *s = avctx->priv_data; + + if (s->pic.data[0]) + avctx->release_buffer(avctx, &s->pic); + + av_freep(&s->y_buffer); + av_freep(&s->scratch_buffer); + + return 0; +} + +AVCodec ff_xan_wc4_decoder = { + "xan_wc4", + AVMEDIA_TYPE_VIDEO, + CODEC_ID_XAN_WC4, + sizeof(XanContext), + xan_decode_init, + NULL, + xan_decode_end, + xan_decode_frame, + CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("Wing Commander IV / Xxan"), +}; + |