| /* |
| * Electronic Arts TGV Video Decoder |
| * Copyright (c) 2007-2008 Peter Ross |
| * |
| * 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 St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * Electronic Arts TGV Video Decoder |
| * by Peter Ross (pross@xvid.org) |
| * |
| * Technical details here: |
| * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGV |
| */ |
| |
| #include "avcodec.h" |
| #define BITSTREAM_READER_LE |
| #include "get_bits.h" |
| #include "internal.h" |
| #include "libavutil/imgutils.h" |
| #include "libavutil/mem.h" |
| |
| #define EA_PREAMBLE_SIZE 8 |
| #define kVGT_TAG MKTAG('k', 'V', 'G', 'T') |
| |
| typedef struct TgvContext { |
| AVCodecContext *avctx; |
| AVFrame *last_frame; |
| uint8_t *frame_buffer; |
| int width,height; |
| uint32_t palette[AVPALETTE_COUNT]; |
| |
| int (*mv_codebook)[2]; |
| uint8_t (*block_codebook)[16]; |
| int num_mvs; ///< current length of mv_codebook |
| int num_blocks_packed; ///< current length of block_codebook |
| } TgvContext; |
| |
| static av_cold int tgv_decode_init(AVCodecContext *avctx) |
| { |
| TgvContext *s = avctx->priv_data; |
| s->avctx = avctx; |
| avctx->framerate = (AVRational){ 15, 1 }; |
| avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| |
| s->last_frame = av_frame_alloc(); |
| if (!s->last_frame) |
| return AVERROR(ENOMEM); |
| |
| return 0; |
| } |
| |
| /** |
| * Unpack buffer |
| * @return 0 on success, -1 on critical buffer underflow |
| */ |
| static int unpack(const uint8_t *src, const uint8_t *src_end, |
| uint8_t *dst, int width, int height) |
| { |
| uint8_t *dst_end = dst + width*height; |
| int size, size1, size2, offset, run; |
| uint8_t *dst_start = dst; |
| |
| if (src[0] & 0x01) |
| src += 5; |
| else |
| src += 2; |
| |
| if (src_end - src < 3) |
| return AVERROR_INVALIDDATA; |
| size = AV_RB24(src); |
| src += 3; |
| |
| while (size > 0 && src < src_end) { |
| |
| /* determine size1 and size2 */ |
| size1 = (src[0] & 3); |
| if (src[0] & 0x80) { // 1 |
| if (src[0] & 0x40 ) { // 11 |
| if (src[0] & 0x20) { // 111 |
| if (src[0] < 0xFC) // !(111111) |
| size1 = (((src[0] & 31) + 1) << 2); |
| src++; |
| size2 = 0; |
| } else { // 110 |
| offset = ((src[0] & 0x10) << 12) + AV_RB16(&src[1]) + 1; |
| size2 = ((src[0] & 0xC) << 6) + src[3] + 5; |
| src += 4; |
| } |
| } else { // 10 |
| size1 = ((src[1] & 0xC0) >> 6); |
| offset = (AV_RB16(&src[1]) & 0x3FFF) + 1; |
| size2 = (src[0] & 0x3F) + 4; |
| src += 3; |
| } |
| } else { // 0 |
| offset = ((src[0] & 0x60) << 3) + src[1] + 1; |
| size2 = ((src[0] & 0x1C) >> 2) + 3; |
| src += 2; |
| } |
| |
| |
| /* fetch strip from src */ |
| if (size1 > src_end - src) |
| break; |
| |
| if (size1 > 0) { |
| size -= size1; |
| run = FFMIN(size1, dst_end - dst); |
| memcpy(dst, src, run); |
| dst += run; |
| src += run; |
| } |
| |
| if (size2 > 0) { |
| if (dst - dst_start < offset) |
| return 0; |
| size -= size2; |
| run = FFMIN(size2, dst_end - dst); |
| av_memcpy_backptr(dst, offset, run); |
| dst += run; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Decode inter-frame |
| * @return 0 on success, -1 on critical buffer underflow |
| */ |
| static int tgv_decode_inter(TgvContext *s, AVFrame *frame, |
| const uint8_t *buf, const uint8_t *buf_end) |
| { |
| int num_mvs; |
| int num_blocks_raw; |
| int num_blocks_packed; |
| int vector_bits; |
| int i,j,x,y; |
| GetBitContext gb; |
| int mvbits; |
| const uint8_t *blocks_raw; |
| |
| if(buf_end - buf < 12) |
| return AVERROR_INVALIDDATA; |
| |
| num_mvs = AV_RL16(&buf[0]); |
| num_blocks_raw = AV_RL16(&buf[2]); |
| num_blocks_packed = AV_RL16(&buf[4]); |
| vector_bits = AV_RL16(&buf[6]); |
| buf += 12; |
| |
| if (vector_bits > MIN_CACHE_BITS || !vector_bits) { |
| av_log(s->avctx, AV_LOG_ERROR, |
| "Invalid value for motion vector bits: %d\n", vector_bits); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* allocate codebook buffers as necessary */ |
| if (num_mvs > s->num_mvs) { |
| int err = av_reallocp_array(&s->mv_codebook, num_mvs, sizeof(*s->mv_codebook)); |
| if (err < 0) { |
| s->num_mvs = 0; |
| return err; |
| } |
| s->num_mvs = num_mvs; |
| } |
| |
| if (num_blocks_packed > s->num_blocks_packed) { |
| int err; |
| if ((err = av_reallocp(&s->block_codebook, num_blocks_packed * 16)) < 0) { |
| s->num_blocks_packed = 0; |
| return err; |
| } |
| s->num_blocks_packed = num_blocks_packed; |
| } |
| |
| /* read motion vectors */ |
| mvbits = (num_mvs * 2 * 10 + 31) & ~31; |
| |
| if (buf_end - buf < (mvbits>>3) + 16*num_blocks_raw + 8*num_blocks_packed) |
| return AVERROR_INVALIDDATA; |
| |
| init_get_bits(&gb, buf, mvbits); |
| for (i = 0; i < num_mvs; i++) { |
| s->mv_codebook[i][0] = get_sbits(&gb, 10); |
| s->mv_codebook[i][1] = get_sbits(&gb, 10); |
| } |
| buf += mvbits >> 3; |
| |
| /* note ptr to uncompressed blocks */ |
| blocks_raw = buf; |
| buf += num_blocks_raw * 16; |
| |
| /* read compressed blocks */ |
| init_get_bits(&gb, buf, (buf_end - buf) << 3); |
| for (i = 0; i < num_blocks_packed; i++) { |
| int tmp[4]; |
| for (j = 0; j < 4; j++) |
| tmp[j] = get_bits(&gb, 8); |
| for (j = 0; j < 16; j++) |
| s->block_codebook[i][15-j] = tmp[get_bits(&gb, 2)]; |
| } |
| |
| if (get_bits_left(&gb) < vector_bits * |
| (s->avctx->height / 4) * (s->avctx->width / 4)) |
| return AVERROR_INVALIDDATA; |
| |
| /* read vectors and build frame */ |
| for (y = 0; y < s->avctx->height / 4; y++) |
| for (x = 0; x < s->avctx->width / 4; x++) { |
| unsigned int vector = get_bits(&gb, vector_bits); |
| const uint8_t *src; |
| int src_stride; |
| |
| if (vector < num_mvs) { |
| int mx = x * 4 + s->mv_codebook[vector][0]; |
| int my = y * 4 + s->mv_codebook[vector][1]; |
| |
| if (mx < 0 || mx + 4 > s->avctx->width || |
| my < 0 || my + 4 > s->avctx->height) { |
| av_log(s->avctx, AV_LOG_ERROR, "MV %d %d out of picture\n", mx, my); |
| continue; |
| } |
| |
| src = s->last_frame->data[0] + mx + my * s->last_frame->linesize[0]; |
| src_stride = s->last_frame->linesize[0]; |
| } else { |
| int offset = vector - num_mvs; |
| if (offset < num_blocks_raw) |
| src = blocks_raw + 16*offset; |
| else if (offset - num_blocks_raw < num_blocks_packed) |
| src = s->block_codebook[offset - num_blocks_raw]; |
| else |
| continue; |
| src_stride = 4; |
| } |
| |
| for (j = 0; j < 4; j++) |
| for (i = 0; i < 4; i++) |
| frame->data[0][(y * 4 + j) * frame->linesize[0] + (x * 4 + i)] = |
| src[j * src_stride + i]; |
| } |
| |
| return 0; |
| } |
| |
| static int tgv_decode_frame(AVCodecContext *avctx, |
| void *data, int *got_frame, |
| AVPacket *avpkt) |
| { |
| const uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| TgvContext *s = avctx->priv_data; |
| const uint8_t *buf_end = buf + buf_size; |
| AVFrame *frame = data; |
| int chunk_type, ret; |
| |
| if (buf_end - buf < EA_PREAMBLE_SIZE) |
| return AVERROR_INVALIDDATA; |
| |
| chunk_type = AV_RL32(&buf[0]); |
| buf += EA_PREAMBLE_SIZE; |
| |
| if (chunk_type == kVGT_TAG) { |
| int pal_count, i; |
| if(buf_end - buf < 12) { |
| av_log(avctx, AV_LOG_WARNING, "truncated header\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| s->width = AV_RL16(&buf[0]); |
| s->height = AV_RL16(&buf[2]); |
| if (s->avctx->width != s->width || s->avctx->height != s->height) { |
| av_freep(&s->frame_buffer); |
| av_frame_unref(s->last_frame); |
| if ((ret = ff_set_dimensions(s->avctx, s->width, s->height)) < 0) |
| return ret; |
| } |
| |
| pal_count = AV_RL16(&buf[6]); |
| buf += 12; |
| for(i = 0; i < pal_count && i < AVPALETTE_COUNT && buf_end - buf >= 3; i++) { |
| s->palette[i] = 0xFFU << 24 | AV_RB24(buf); |
| buf += 3; |
| } |
| } |
| |
| if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) |
| return ret; |
| |
| memcpy(frame->data[1], s->palette, AVPALETTE_SIZE); |
| |
| if (chunk_type == kVGT_TAG) { |
| int y; |
| frame->key_frame = 1; |
| frame->pict_type = AV_PICTURE_TYPE_I; |
| |
| if (!s->frame_buffer && |
| !(s->frame_buffer = av_mallocz(s->width * s->height))) |
| return AVERROR(ENOMEM); |
| |
| if (unpack(buf, buf_end, s->frame_buffer, s->avctx->width, s->avctx->height) < 0) { |
| av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| for (y = 0; y < s->height; y++) |
| memcpy(frame->data[0] + y * frame->linesize[0], |
| s->frame_buffer + y * s->width, |
| s->width); |
| } else { |
| if (!s->last_frame->data[0]) { |
| av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n"); |
| return buf_size; |
| } |
| frame->key_frame = 0; |
| frame->pict_type = AV_PICTURE_TYPE_P; |
| if (tgv_decode_inter(s, frame, buf, buf_end) < 0) { |
| av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| } |
| |
| av_frame_unref(s->last_frame); |
| if ((ret = av_frame_ref(s->last_frame, frame)) < 0) |
| return ret; |
| |
| *got_frame = 1; |
| |
| return buf_size; |
| } |
| |
| static av_cold int tgv_decode_end(AVCodecContext *avctx) |
| { |
| TgvContext *s = avctx->priv_data; |
| av_frame_free(&s->last_frame); |
| av_freep(&s->frame_buffer); |
| av_freep(&s->mv_codebook); |
| av_freep(&s->block_codebook); |
| return 0; |
| } |
| |
| AVCodec ff_eatgv_decoder = { |
| .name = "eatgv", |
| .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGV video"), |
| .type = AVMEDIA_TYPE_VIDEO, |
| .id = AV_CODEC_ID_TGV, |
| .priv_data_size = sizeof(TgvContext), |
| .init = tgv_decode_init, |
| .close = tgv_decode_end, |
| .decode = tgv_decode_frame, |
| .capabilities = AV_CODEC_CAP_DR1, |
| }; |
