| /* |
| * Cinepak Video Decoder |
| * Copyright (C) 2003 the ffmpeg project |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * Cinepak video decoder |
| * by Ewald Snel <ewald@rambo.its.tudelft.nl> |
| * For more information on the Cinepak algorithm, visit: |
| * http://www.csse.monash.edu.au/~timf/ |
| * For more information on the quirky data inside Sega FILM/CPK files, visit: |
| * http://wiki.multimedia.cx/index.php?title=Sega_FILM |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "libavutil/intreadwrite.h" |
| #include "avcodec.h" |
| |
| |
| typedef struct { |
| uint8_t y0, y1, y2, y3; |
| uint8_t u, v; |
| } cvid_codebook; |
| |
| #define MAX_STRIPS 32 |
| |
| typedef struct { |
| uint16_t id; |
| uint16_t x1, y1; |
| uint16_t x2, y2; |
| cvid_codebook v4_codebook[256]; |
| cvid_codebook v1_codebook[256]; |
| } cvid_strip; |
| |
| typedef struct CinepakContext { |
| |
| AVCodecContext *avctx; |
| AVFrame frame; |
| |
| const unsigned char *data; |
| int size; |
| |
| int width, height; |
| |
| int palette_video; |
| cvid_strip strips[MAX_STRIPS]; |
| |
| int sega_film_skip_bytes; |
| |
| } CinepakContext; |
| |
| static void cinepak_decode_codebook (cvid_codebook *codebook, |
| int chunk_id, int size, const uint8_t *data) |
| { |
| const uint8_t *eod = (data + size); |
| uint32_t flag, mask; |
| int i, n; |
| |
| /* check if this chunk contains 4- or 6-element vectors */ |
| n = (chunk_id & 0x04) ? 4 : 6; |
| flag = 0; |
| mask = 0; |
| |
| for (i=0; i < 256; i++) { |
| if ((chunk_id & 0x01) && !(mask >>= 1)) { |
| if ((data + 4) > eod) |
| break; |
| |
| flag = AV_RB32 (data); |
| data += 4; |
| mask = 0x80000000; |
| } |
| |
| if (!(chunk_id & 0x01) || (flag & mask)) { |
| if ((data + n) > eod) |
| break; |
| |
| if (n == 6) { |
| codebook[i].y0 = *data++; |
| codebook[i].y1 = *data++; |
| codebook[i].y2 = *data++; |
| codebook[i].y3 = *data++; |
| codebook[i].u = 128 + *data++; |
| codebook[i].v = 128 + *data++; |
| } else { |
| /* this codebook type indicates either greyscale or |
| * palettized video; if palettized, U & V components will |
| * not be used so it is safe to set them to 128 for the |
| * benefit of greyscale rendering in YUV420P */ |
| codebook[i].y0 = *data++; |
| codebook[i].y1 = *data++; |
| codebook[i].y2 = *data++; |
| codebook[i].y3 = *data++; |
| codebook[i].u = 128; |
| codebook[i].v = 128; |
| } |
| } |
| } |
| } |
| |
| static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip, |
| int chunk_id, int size, const uint8_t *data) |
| { |
| const uint8_t *eod = (data + size); |
| uint32_t flag, mask; |
| cvid_codebook *codebook; |
| unsigned int x, y; |
| uint32_t iy[4]; |
| uint32_t iu[2]; |
| uint32_t iv[2]; |
| |
| flag = 0; |
| mask = 0; |
| |
| for (y=strip->y1; y < strip->y2; y+=4) { |
| |
| iy[0] = strip->x1 + (y * s->frame.linesize[0]); |
| iy[1] = iy[0] + s->frame.linesize[0]; |
| iy[2] = iy[1] + s->frame.linesize[0]; |
| iy[3] = iy[2] + s->frame.linesize[0]; |
| iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]); |
| iu[1] = iu[0] + s->frame.linesize[1]; |
| iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]); |
| iv[1] = iv[0] + s->frame.linesize[2]; |
| |
| for (x=strip->x1; x < strip->x2; x+=4) { |
| if ((chunk_id & 0x01) && !(mask >>= 1)) { |
| if ((data + 4) > eod) |
| return -1; |
| |
| flag = AV_RB32 (data); |
| data += 4; |
| mask = 0x80000000; |
| } |
| |
| if (!(chunk_id & 0x01) || (flag & mask)) { |
| if (!(chunk_id & 0x02) && !(mask >>= 1)) { |
| if ((data + 4) > eod) |
| return -1; |
| |
| flag = AV_RB32 (data); |
| data += 4; |
| mask = 0x80000000; |
| } |
| |
| if ((chunk_id & 0x02) || (~flag & mask)) { |
| if (data >= eod) |
| return -1; |
| |
| codebook = &strip->v1_codebook[*data++]; |
| s->frame.data[0][iy[0] + 0] = codebook->y0; |
| s->frame.data[0][iy[0] + 1] = codebook->y0; |
| s->frame.data[0][iy[1] + 0] = codebook->y0; |
| s->frame.data[0][iy[1] + 1] = codebook->y0; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[0]] = codebook->u; |
| s->frame.data[2][iv[0]] = codebook->v; |
| } |
| |
| s->frame.data[0][iy[0] + 2] = codebook->y1; |
| s->frame.data[0][iy[0] + 3] = codebook->y1; |
| s->frame.data[0][iy[1] + 2] = codebook->y1; |
| s->frame.data[0][iy[1] + 3] = codebook->y1; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[0] + 1] = codebook->u; |
| s->frame.data[2][iv[0] + 1] = codebook->v; |
| } |
| |
| s->frame.data[0][iy[2] + 0] = codebook->y2; |
| s->frame.data[0][iy[2] + 1] = codebook->y2; |
| s->frame.data[0][iy[3] + 0] = codebook->y2; |
| s->frame.data[0][iy[3] + 1] = codebook->y2; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[1]] = codebook->u; |
| s->frame.data[2][iv[1]] = codebook->v; |
| } |
| |
| s->frame.data[0][iy[2] + 2] = codebook->y3; |
| s->frame.data[0][iy[2] + 3] = codebook->y3; |
| s->frame.data[0][iy[3] + 2] = codebook->y3; |
| s->frame.data[0][iy[3] + 3] = codebook->y3; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[1] + 1] = codebook->u; |
| s->frame.data[2][iv[1] + 1] = codebook->v; |
| } |
| |
| } else if (flag & mask) { |
| if ((data + 4) > eod) |
| return -1; |
| |
| codebook = &strip->v4_codebook[*data++]; |
| s->frame.data[0][iy[0] + 0] = codebook->y0; |
| s->frame.data[0][iy[0] + 1] = codebook->y1; |
| s->frame.data[0][iy[1] + 0] = codebook->y2; |
| s->frame.data[0][iy[1] + 1] = codebook->y3; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[0]] = codebook->u; |
| s->frame.data[2][iv[0]] = codebook->v; |
| } |
| |
| codebook = &strip->v4_codebook[*data++]; |
| s->frame.data[0][iy[0] + 2] = codebook->y0; |
| s->frame.data[0][iy[0] + 3] = codebook->y1; |
| s->frame.data[0][iy[1] + 2] = codebook->y2; |
| s->frame.data[0][iy[1] + 3] = codebook->y3; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[0] + 1] = codebook->u; |
| s->frame.data[2][iv[0] + 1] = codebook->v; |
| } |
| |
| codebook = &strip->v4_codebook[*data++]; |
| s->frame.data[0][iy[2] + 0] = codebook->y0; |
| s->frame.data[0][iy[2] + 1] = codebook->y1; |
| s->frame.data[0][iy[3] + 0] = codebook->y2; |
| s->frame.data[0][iy[3] + 1] = codebook->y3; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[1]] = codebook->u; |
| s->frame.data[2][iv[1]] = codebook->v; |
| } |
| |
| codebook = &strip->v4_codebook[*data++]; |
| s->frame.data[0][iy[2] + 2] = codebook->y0; |
| s->frame.data[0][iy[2] + 3] = codebook->y1; |
| s->frame.data[0][iy[3] + 2] = codebook->y2; |
| s->frame.data[0][iy[3] + 3] = codebook->y3; |
| if (!s->palette_video) { |
| s->frame.data[1][iu[1] + 1] = codebook->u; |
| s->frame.data[2][iv[1] + 1] = codebook->v; |
| } |
| |
| } |
| } |
| |
| iy[0] += 4; iy[1] += 4; |
| iy[2] += 4; iy[3] += 4; |
| iu[0] += 2; iu[1] += 2; |
| iv[0] += 2; iv[1] += 2; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int cinepak_decode_strip (CinepakContext *s, |
| cvid_strip *strip, const uint8_t *data, int size) |
| { |
| const uint8_t *eod = (data + size); |
| int chunk_id, chunk_size; |
| |
| /* coordinate sanity checks */ |
| if (strip->x1 >= s->width || strip->x2 > s->width || |
| strip->y1 >= s->height || strip->y2 > s->height || |
| strip->x1 >= strip->x2 || strip->y1 >= strip->y2) |
| return -1; |
| |
| while ((data + 4) <= eod) { |
| chunk_id = data[0]; |
| chunk_size = AV_RB24 (&data[1]) - 4; |
| if(chunk_size < 0) |
| return -1; |
| |
| data += 4; |
| chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size; |
| |
| switch (chunk_id) { |
| |
| case 0x20: |
| case 0x21: |
| case 0x24: |
| case 0x25: |
| cinepak_decode_codebook (strip->v4_codebook, chunk_id, |
| chunk_size, data); |
| break; |
| |
| case 0x22: |
| case 0x23: |
| case 0x26: |
| case 0x27: |
| cinepak_decode_codebook (strip->v1_codebook, chunk_id, |
| chunk_size, data); |
| break; |
| |
| case 0x30: |
| case 0x31: |
| case 0x32: |
| return cinepak_decode_vectors (s, strip, chunk_id, |
| chunk_size, data); |
| } |
| |
| data += chunk_size; |
| } |
| |
| return -1; |
| } |
| |
| static int cinepak_decode (CinepakContext *s) |
| { |
| const uint8_t *eod = (s->data + s->size); |
| int i, result, strip_size, frame_flags, num_strips; |
| int y0 = 0; |
| int encoded_buf_size; |
| |
| if (s->size < 10) |
| return -1; |
| |
| frame_flags = s->data[0]; |
| num_strips = AV_RB16 (&s->data[8]); |
| encoded_buf_size = ((s->data[1] << 16) | AV_RB16 (&s->data[2])); |
| |
| /* if this is the first frame, check for deviant Sega FILM data */ |
| if (s->sega_film_skip_bytes == -1) { |
| if (encoded_buf_size != s->size) { |
| /* If the encoded frame size differs from the frame size as indicated |
| * by the container file, this data likely comes from a Sega FILM/CPK file. |
| * If the frame header is followed by the bytes FE 00 00 06 00 00 then |
| * this is probably one of the two known files that have 6 extra bytes |
| * after the frame header. Else, assume 2 extra bytes. */ |
| if (s->size >= 16 && |
| (s->data[10] == 0xFE) && |
| (s->data[11] == 0x00) && |
| (s->data[12] == 0x00) && |
| (s->data[13] == 0x06) && |
| (s->data[14] == 0x00) && |
| (s->data[15] == 0x00)) |
| s->sega_film_skip_bytes = 6; |
| else |
| s->sega_film_skip_bytes = 2; |
| } else |
| s->sega_film_skip_bytes = 0; |
| } |
| |
| s->data += 10 + s->sega_film_skip_bytes; |
| |
| if (num_strips > MAX_STRIPS) |
| num_strips = MAX_STRIPS; |
| |
| for (i=0; i < num_strips; i++) { |
| if ((s->data + 12) > eod) |
| return -1; |
| |
| s->strips[i].id = s->data[0]; |
| s->strips[i].y1 = y0; |
| s->strips[i].x1 = 0; |
| s->strips[i].y2 = y0 + AV_RB16 (&s->data[8]); |
| s->strips[i].x2 = s->avctx->width; |
| |
| strip_size = AV_RB24 (&s->data[1]) - 12; |
| if(strip_size < 0) |
| return -1; |
| s->data += 12; |
| strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size; |
| |
| if ((i > 0) && !(frame_flags & 0x01)) { |
| memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook, |
| sizeof(s->strips[i].v4_codebook)); |
| memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook, |
| sizeof(s->strips[i].v1_codebook)); |
| } |
| |
| result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size); |
| |
| if (result != 0) |
| return result; |
| |
| s->data += strip_size; |
| y0 = s->strips[i].y2; |
| } |
| return 0; |
| } |
| |
| static av_cold int cinepak_decode_init(AVCodecContext *avctx) |
| { |
| CinepakContext *s = avctx->priv_data; |
| |
| s->avctx = avctx; |
| s->width = (avctx->width + 3) & ~3; |
| s->height = (avctx->height + 3) & ~3; |
| s->sega_film_skip_bytes = -1; /* uninitialized state */ |
| |
| // check for paletted data |
| if ((avctx->palctrl == NULL) || (avctx->bits_per_coded_sample == 40)) { |
| s->palette_video = 0; |
| avctx->pix_fmt = PIX_FMT_YUV420P; |
| } else { |
| s->palette_video = 1; |
| avctx->pix_fmt = PIX_FMT_PAL8; |
| } |
| |
| avcodec_get_frame_defaults(&s->frame); |
| s->frame.data[0] = NULL; |
| |
| return 0; |
| } |
| |
| static int cinepak_decode_frame(AVCodecContext *avctx, |
| void *data, int *data_size, |
| AVPacket *avpkt) |
| { |
| const uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| CinepakContext *s = avctx->priv_data; |
| |
| s->data = buf; |
| s->size = buf_size; |
| |
| s->frame.reference = 1; |
| s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | |
| FF_BUFFER_HINTS_REUSABLE; |
| if (avctx->reget_buffer(avctx, &s->frame)) { |
| av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); |
| return -1; |
| } |
| |
| cinepak_decode(s); |
| |
| if (s->palette_video) { |
| memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE); |
| if (avctx->palctrl->palette_changed) { |
| s->frame.palette_has_changed = 1; |
| avctx->palctrl->palette_changed = 0; |
| } else |
| s->frame.palette_has_changed = 0; |
| } |
| |
| *data_size = sizeof(AVFrame); |
| *(AVFrame*)data = s->frame; |
| |
| /* report that the buffer was completely consumed */ |
| return buf_size; |
| } |
| |
| static av_cold int cinepak_decode_end(AVCodecContext *avctx) |
| { |
| CinepakContext *s = avctx->priv_data; |
| |
| if (s->frame.data[0]) |
| avctx->release_buffer(avctx, &s->frame); |
| |
| return 0; |
| } |
| |
| AVCodec ff_cinepak_decoder = { |
| "cinepak", |
| AVMEDIA_TYPE_VIDEO, |
| CODEC_ID_CINEPAK, |
| sizeof(CinepakContext), |
| cinepak_decode_init, |
| NULL, |
| cinepak_decode_end, |
| cinepak_decode_frame, |
| CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("Cinepak"), |
| }; |