diff options
Diffstat (limited to 'libavcodec/eacmv.c')
| -rw-r--r-- | libavcodec/eacmv.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/libavcodec/eacmv.c b/libavcodec/eacmv.c new file mode 100644 index 0000000000..a9f624e046 --- /dev/null +++ b/libavcodec/eacmv.c @@ -0,0 +1,214 @@ +/* + * Electronic Arts CMV 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 eacmv.c + * Electronic Arts CMV Video Decoder + * by Peter Ross (suxen_drol at hotmail dot com) + * + * Technical details here: + * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_CMV + */ + +#include "avcodec.h" + +typedef struct CmvContext { + AVCodecContext *avctx; + AVFrame frame; ///< current + AVFrame last_frame; ///< last + AVFrame last2_frame; ///< second-last + int width, height; + unsigned int palette[AVPALETTE_COUNT]; +} CmvContext; + +static av_cold int cmv_decode_init(AVCodecContext *avctx){ + CmvContext *s = avctx->priv_data; + s->avctx = avctx; + avctx->pix_fmt = PIX_FMT_PAL8; + return 0; +} + +static void cmv_decode_intra(CmvContext * s, const uint8_t *buf, const uint8_t *buf_end){ + unsigned char *dst = s->frame.data[0]; + int i; + + for (i=0; i < s->avctx->height && buf+s->avctx->width<=buf_end; i++) { + memcpy(dst, buf, s->avctx->width); + dst += s->frame.linesize[0]; + buf += s->avctx->width; + } +} + +static void cmv_motcomp(unsigned char *dst, int dst_stride, + const unsigned char *src, int src_stride, + int x, int y, + int xoffset, int yoffset, + int width, int height){ + int i,j; + + for(j=y;j<y+4;j++) + for(i=x;i<x+4;i++) + { + if (i+xoffset>=0 && i+xoffset<width && + j+yoffset>=0 && j+yoffset<height) { + dst[j*dst_stride + i] = src[(j+yoffset)*src_stride + i+xoffset]; + }else{ + dst[j*dst_stride + i] = 0; + } + } +} + +static void cmv_decode_inter(CmvContext * s, const uint8_t *buf, const uint8_t *buf_end){ + const uint8_t *raw = buf + (s->avctx->width*s->avctx->height/16); + int x,y,i; + + i = 0; + for(y=0; y<s->avctx->height/4; y++) + for(x=0; x<s->avctx->width/4 && buf+i<buf_end; x++) { + if (buf[i]==0xFF) { + unsigned char *dst = s->frame.data[0] + (y*4)*s->frame.linesize[0] + x*4; + if (raw+16<buf_end && *raw==0xFF) { /* intra */ + raw++; + memcpy(dst, raw, 4); + memcpy(dst+s->frame.linesize[0], raw+4, 4); + memcpy(dst+2*s->frame.linesize[0], raw+8, 4); + memcpy(dst+3*s->frame.linesize[0], raw+12, 4); + raw+=16; + }else if(raw<buf_end) { /* inter using second-last frame as reference */ + int xoffset = (*raw & 0xF) - 7; + int yoffset = ((*raw >> 4)) - 7; + cmv_motcomp(s->frame.data[0], s->frame.linesize[0], + s->last2_frame.data[0], s->last2_frame.linesize[0], + x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height); + raw++; + } + }else{ /* inter using last frame as reference */ + int xoffset = (buf[i] & 0xF) - 7; + int yoffset = ((buf[i] >> 4)) - 7; + cmv_motcomp(s->frame.data[0], s->frame.linesize[0], + s->last_frame.data[0], s->last_frame.linesize[0], + x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height); + } + i++; + } +} + +static void cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end) +{ + int pal_start, pal_count, i; + + if(buf+16>=buf_end) { + av_log(s->avctx, AV_LOG_WARNING, "truncated header\n"); + return; + } + + s->width = AV_RL16(&buf[4]); + s->height = AV_RL16(&buf[6]); + if (s->avctx->width!=s->width || s->avctx->height!=s->height) + avcodec_set_dimensions(s->avctx, s->width, s->height); + + s->avctx->time_base.num = 1; + s->avctx->time_base.den = AV_RL16(&buf[10]); + + pal_start = AV_RL16(&buf[12]); + pal_count = AV_RL16(&buf[14]); + + buf += 16; + for (i=pal_start; i<pal_start+pal_count && i<AVPALETTE_COUNT && buf+2<buf_end; i++) { + s->palette[i] = AV_RB24(buf); + buf += 3; + } +} + +#define EA_PREAMBLE_SIZE 8 +#define MVIh_TAG MKTAG('M', 'V', 'I', 'h') + +static int cmv_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + const uint8_t *buf, int buf_size) +{ + CmvContext *s = avctx->priv_data; + const uint8_t *buf_end = buf + buf_size; + + if (AV_RL32(buf)==MVIh_TAG||AV_RB32(buf)==MVIh_TAG) { + cmv_process_header(s, buf+EA_PREAMBLE_SIZE, buf_end); + return buf_size; + } + + if (avcodec_check_dimensions(s->avctx, s->width, s->height)) + return -1; + + /* shuffle */ + if (s->last2_frame.data[0]) + avctx->release_buffer(avctx, &s->last2_frame); + FFSWAP(AVFrame, s->last_frame, s->last2_frame); + FFSWAP(AVFrame, s->frame, s->last_frame); + + s->frame.reference = 1; + s->frame.buffer_hints = FF_BUFFER_HINTS_VALID; + if (avctx->get_buffer(avctx, &s->frame)<0) { + av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + return -1; + } + + memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); + + buf += EA_PREAMBLE_SIZE; + if ((buf[0]&1)) { // subtype + cmv_decode_inter(s, buf+2, buf_end); + s->frame.key_frame = 0; + s->frame.pict_type = FF_P_TYPE; + }else{ + s->frame.key_frame = 1; + s->frame.pict_type = FF_I_TYPE; + cmv_decode_intra(s, buf+2, buf_end); + } + + *data_size = sizeof(AVFrame); + *(AVFrame*)data = s->frame; + + return buf_size; +} + +static av_cold int cmv_decode_end(AVCodecContext *avctx){ + CmvContext *s = avctx->priv_data; + if (s->frame.data[0]) + s->avctx->release_buffer(avctx, &s->frame); + if (s->last_frame.data[0]) + s->avctx->release_buffer(avctx, &s->last_frame); + if (s->last2_frame.data[0]) + s->avctx->release_buffer(avctx, &s->last2_frame); + + return 0; +} + +AVCodec eacmv_decoder = { + "eacmv", + CODEC_TYPE_VIDEO, + CODEC_ID_CMV, + sizeof(CmvContext), + cmv_decode_init, + NULL, + cmv_decode_end, + cmv_decode_frame, + CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts CMV Video"), +}; |