/* * Intel Indeo 2 codec * Copyright (c) 2005 Konstantin Shishkov * * 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 libavcodec/indeo2.c * Intel Indeo 2 decoder. */ #define ALT_BITSTREAM_READER_LE #include "avcodec.h" #include "get_bits.h" #include "indeo2data.h" typedef struct Ir2Context{ AVCodecContext *avctx; AVFrame picture; GetBitContext gb; int decode_delta; } Ir2Context; #define CODE_VLC_BITS 14 static VLC ir2_vlc; /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */ static inline int ir2_get_code(GetBitContext *gb) { return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1; } static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride, const uint8_t *table) { int i; int j; int out = 0; int c; int t; if(width&1) return -1; /* first line contain absolute values, other lines contain deltas */ while (out < width){ c = ir2_get_code(&ctx->gb); if(c >= 0x80) { /* we have a run */ c -= 0x7F; if(out + c*2 > width) return -1; for (i = 0; i < c * 2; i++) dst[out++] = 0x80; } else { /* copy two values from table */ dst[out++] = table[c * 2]; dst[out++] = table[(c * 2) + 1]; } } dst += stride; for (j = 1; j < height; j++){ out = 0; while (out < width){ c = ir2_get_code(&ctx->gb); if(c >= 0x80) { /* we have a skip */ c -= 0x7F; if(out + c*2 > width) return -1; for (i = 0; i < c * 2; i++) { dst[out] = dst[out - stride]; out++; } } else { /* add two deltas from table */ t = dst[out - stride] + (table[c * 2] - 128); t= av_clip_uint8(t); dst[out] = t; out++; t = dst[out - stride] + (table[(c * 2) + 1] - 128); t= av_clip_uint8(t); dst[out] = t; out++; } } dst += stride; } return 0; } static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride, const uint8_t *table) { int j; int out = 0; int c; int t; if(width&1) return -1; for (j = 0; j < height; j++){ out = 0; while (out < width){ c = ir2_get_code(&ctx->gb); if(c >= 0x80) { /* we have a skip */ c -= 0x7F; out += c * 2; } else { /* add two deltas from table */ t = dst[out] + (((table[c * 2] - 128)*3) >> 2); t= av_clip_uint8(t); dst[out] = t; out++; t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2); t= av_clip_uint8(t); dst[out] = t; out++; } } dst += stride; } return 0; } static int ir2_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; Ir2Context * const s = avctx->priv_data; AVFrame *picture = data; AVFrame * const p= (AVFrame*)&s->picture; int start; if(p->data[0]) avctx->release_buffer(avctx, p); p->reference = 1; p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; if (avctx->reget_buffer(avctx, p)) { av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } s->decode_delta = buf[18]; /* decide whether frame uses deltas or not */ #ifndef ALT_BITSTREAM_READER_LE for (i = 0; i < buf_size; i++) buf[i] = ff_reverse[buf[i]]; #endif start = 48; /* hardcoded for now */ init_get_bits(&s->gb, buf + start, buf_size - start); if (s->decode_delta) { /* intraframe */ ir2_decode_plane(s, avctx->width, avctx->height, s->picture.data[0], s->picture.linesize[0], ir2_luma_table); /* swapped U and V */ ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2, s->picture.data[2], s->picture.linesize[2], ir2_luma_table); ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2, s->picture.data[1], s->picture.linesize[1], ir2_luma_table); } else { /* interframe */ ir2_decode_plane_inter(s, avctx->width, avctx->height, s->picture.data[0], s->picture.linesize[0], ir2_luma_table); /* swapped U and V */ ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2, s->picture.data[2], s->picture.linesize[2], ir2_luma_table); ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2, s->picture.data[1], s->picture.linesize[1], ir2_luma_table); } *picture= *(AVFrame*)&s->picture; *data_size = sizeof(AVPicture); return buf_size; } static av_cold int ir2_decode_init(AVCodecContext *avctx){ Ir2Context * const ic = avctx->priv_data; static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2]; ic->avctx = avctx; avctx->pix_fmt= PIX_FMT_YUV410P; ir2_vlc.table = vlc_tables; ir2_vlc.table_allocated = 1 << CODE_VLC_BITS; #ifdef ALT_BITSTREAM_READER_LE init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES, &ir2_codes[0][1], 4, 2, &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE); #else init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES, &ir2_codes[0][1], 4, 2, &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC); #endif return 0; } static av_cold int ir2_decode_end(AVCodecContext *avctx){ Ir2Context * const ic = avctx->priv_data; AVFrame *pic = &ic->picture; if (pic->data[0]) avctx->release_buffer(avctx, pic); av_freep(&ic->picture); return 0; } AVCodec indeo2_decoder = { "indeo2", CODEC_TYPE_VIDEO, CODEC_ID_INDEO2, sizeof(Ir2Context), ir2_decode_init, NULL, ir2_decode_end, ir2_decode_frame, CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"), };