| /* | |
| * Escape 130 video decoder | |
| * Copyright (C) 2008 Eli Friedman (eli.friedman <at> gmail.com) | |
| * | |
| * 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 "libavutil/attributes.h" | |
| #include "libavutil/mem.h" | |
| #define BITSTREAM_READER_LE | |
| #include "avcodec.h" | |
| #include "codec_internal.h" | |
| #include "decode.h" | |
| #include "get_bits.h" | |
| typedef struct Escape130Context { | |
| uint8_t *old_y_avg; | |
| uint8_t *new_y, *old_y; | |
| uint8_t *new_u, *old_u; | |
| uint8_t *new_v, *old_v; | |
| uint8_t *buf1, *buf2; | |
| int linesize[3]; | |
| } Escape130Context; | |
| static const uint8_t offset_table[] = { 2, 4, 10, 20 }; | |
| static const int8_t sign_table[64][4] = { | |
| { 0, 0, 0, 0 }, | |
| { -1, 1, 0, 0 }, | |
| { 1, -1, 0, 0 }, | |
| { -1, 0, 1, 0 }, | |
| { -1, 1, 1, 0 }, | |
| { 0, -1, 1, 0 }, | |
| { 1, -1, 1, 0 }, | |
| { -1, -1, 1, 0 }, | |
| { 1, 0, -1, 0 }, | |
| { 0, 1, -1, 0 }, | |
| { 1, 1, -1, 0 }, | |
| { -1, 1, -1, 0 }, | |
| { 1, -1, -1, 0 }, | |
| { -1, 0, 0, 1 }, | |
| { -1, 1, 0, 1 }, | |
| { 0, -1, 0, 1 }, | |
| { 0, 0, 0, 0 }, | |
| { 1, -1, 0, 1 }, | |
| { -1, -1, 0, 1 }, | |
| { -1, 0, 1, 1 }, | |
| { -1, 1, 1, 1 }, | |
| { 0, -1, 1, 1 }, | |
| { 1, -1, 1, 1 }, | |
| { -1, -1, 1, 1 }, | |
| { 0, 0, -1, 1 }, | |
| { 1, 0, -1, 1 }, | |
| { -1, 0, -1, 1 }, | |
| { 0, 1, -1, 1 }, | |
| { 1, 1, -1, 1 }, | |
| { -1, 1, -1, 1 }, | |
| { 0, -1, -1, 1 }, | |
| { 1, -1, -1, 1 }, | |
| { 0, 0, 0, 0 }, | |
| { -1, -1, -1, 1 }, | |
| { 1, 0, 0, -1 }, | |
| { 0, 1, 0, -1 }, | |
| { 1, 1, 0, -1 }, | |
| { -1, 1, 0, -1 }, | |
| { 1, -1, 0, -1 }, | |
| { 0, 0, 1, -1 }, | |
| { 1, 0, 1, -1 }, | |
| { -1, 0, 1, -1 }, | |
| { 0, 1, 1, -1 }, | |
| { 1, 1, 1, -1 }, | |
| { -1, 1, 1, -1 }, | |
| { 0, -1, 1, -1 }, | |
| { 1, -1, 1, -1 }, | |
| { -1, -1, 1, -1 }, | |
| { 0, 0, 0, 0 }, | |
| { 1, 0, -1, -1 }, | |
| { 0, 1, -1, -1 }, | |
| { 1, 1, -1, -1 }, | |
| { -1, 1, -1, -1 }, | |
| { 1, -1, -1, -1 } | |
| }; | |
| static const int8_t luma_adjust[] = { -4, -3, -2, -1, 1, 2, 3, 4 }; | |
| static const int8_t chroma_adjust[2][8] = { | |
| { 1, 1, 0, -1, -1, -1, 0, 1 }, | |
| { 0, 1, 1, 1, 0, -1, -1, -1 } | |
| }; | |
| static const uint8_t chroma_vals[] = { | |
| 20, 28, 36, 44, 52, 60, 68, 76, | |
| 84, 92, 100, 106, 112, 116, 120, 124, | |
| 128, 132, 136, 140, 144, 150, 156, 164, | |
| 172, 180, 188, 196, 204, 212, 220, 228 | |
| }; | |
| static av_cold int escape130_decode_init(AVCodecContext *avctx) | |
| { | |
| Escape130Context *s = avctx->priv_data; | |
| avctx->pix_fmt = AV_PIX_FMT_YUV420P; | |
| if ((avctx->width & 1) || (avctx->height & 1)) { | |
| av_log(avctx, AV_LOG_ERROR, | |
| "Dimensions should be a multiple of two.\n"); | |
| return AVERROR_INVALIDDATA; | |
| } | |
| s->old_y_avg = av_malloc(avctx->width * avctx->height / 4); | |
| s->buf1 = av_malloc(avctx->width * avctx->height * 3 / 2); | |
| s->buf2 = av_malloc(avctx->width * avctx->height * 3 / 2); | |
| if (!s->old_y_avg || !s->buf1 || !s->buf2) { | |
| av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n"); | |
| return AVERROR(ENOMEM); | |
| } | |
| s->linesize[0] = avctx->width; | |
| s->linesize[1] = | |
| s->linesize[2] = avctx->width / 2; | |
| s->new_y = s->buf1; | |
| s->new_u = s->new_y + avctx->width * avctx->height; | |
| s->new_v = s->new_u + avctx->width * avctx->height / 4; | |
| s->old_y = s->buf2; | |
| s->old_u = s->old_y + avctx->width * avctx->height; | |
| s->old_v = s->old_u + avctx->width * avctx->height / 4; | |
| memset(s->old_y, 0, avctx->width * avctx->height); | |
| memset(s->old_u, 0x10, avctx->width * avctx->height / 4); | |
| memset(s->old_v, 0x10, avctx->width * avctx->height / 4); | |
| return 0; | |
| } | |
| static av_cold int escape130_decode_close(AVCodecContext *avctx) | |
| { | |
| Escape130Context *s = avctx->priv_data; | |
| av_freep(&s->old_y_avg); | |
| av_freep(&s->buf1); | |
| av_freep(&s->buf2); | |
| return 0; | |
| } | |
| static int decode_skip_count(GetBitContext* gb) | |
| { | |
| int value; | |
| if (get_bits_left(gb) < 1+3) | |
| return -1; | |
| value = get_bits1(gb); | |
| if (value) | |
| return 0; | |
| value = get_bits(gb, 3); | |
| if (value) | |
| return value; | |
| value = get_bits(gb, 8); | |
| if (value) | |
| return value + 7; | |
| value = get_bits(gb, 15); | |
| if (value) | |
| return value + 262; | |
| return -1; | |
| } | |
| static int escape130_decode_frame(AVCodecContext *avctx, AVFrame *pic, | |
| int *got_frame, AVPacket *avpkt) | |
| { | |
| int buf_size = avpkt->size; | |
| Escape130Context *s = avctx->priv_data; | |
| GetBitContext gb; | |
| int ret; | |
| uint8_t *old_y, *old_cb, *old_cr, | |
| *new_y, *new_cb, *new_cr; | |
| uint8_t *dstY, *dstU, *dstV; | |
| unsigned old_y_stride, old_cb_stride, old_cr_stride, | |
| new_y_stride, new_cb_stride, new_cr_stride; | |
| unsigned total_blocks = avctx->width * avctx->height / 4, | |
| block_index, block_x = 0; | |
| unsigned y[4] = { 0 }, cb = 0x10, cr = 0x10; | |
| int skip = -1, y_avg = 0, i, j; | |
| uint8_t *ya = s->old_y_avg; | |
| // first 16 bytes are header; no useful information in here | |
| if (buf_size <= 16) { | |
| av_log(avctx, AV_LOG_ERROR, "Insufficient frame data\n"); | |
| return AVERROR_INVALIDDATA; | |
| } | |
| if ((ret = ff_get_buffer(avctx, pic, 0)) < 0) | |
| return ret; | |
| if ((ret = init_get_bits8(&gb, avpkt->data, avpkt->size)) < 0) | |
| return ret; | |
| skip_bits_long(&gb, 16 * 8); | |
| new_y = s->new_y; | |
| new_cb = s->new_u; | |
| new_cr = s->new_v; | |
| new_y_stride = s->linesize[0]; | |
| new_cb_stride = s->linesize[1]; | |
| new_cr_stride = s->linesize[2]; | |
| old_y = s->old_y; | |
| old_cb = s->old_u; | |
| old_cr = s->old_v; | |
| old_y_stride = s->linesize[0]; | |
| old_cb_stride = s->linesize[1]; | |
| old_cr_stride = s->linesize[2]; | |
| for (block_index = 0; block_index < total_blocks; block_index++) { | |
| // Note that this call will make us skip the rest of the blocks | |
| // if the frame ends prematurely. | |
| if (skip == -1) | |
| skip = decode_skip_count(&gb); | |
| if (skip == -1) { | |
| av_log(avctx, AV_LOG_ERROR, "Error decoding skip value\n"); | |
| return AVERROR_INVALIDDATA; | |
| } | |
| if (skip) { | |
| y[0] = old_y[0]; | |
| y[1] = old_y[1]; | |
| y[2] = old_y[old_y_stride]; | |
| y[3] = old_y[old_y_stride + 1]; | |
| y_avg = ya[0]; | |
| cb = old_cb[0]; | |
| cr = old_cr[0]; | |
| } else { | |
| if (get_bits1(&gb)) { | |
| unsigned sign_selector = get_bits(&gb, 6); | |
| unsigned difference_selector = get_bits(&gb, 2); | |
| y_avg = 2 * get_bits(&gb, 5); | |
| for (i = 0; i < 4; i++) { | |
| y[i] = av_clip(y_avg + offset_table[difference_selector] * | |
| sign_table[sign_selector][i], 0, 63); | |
| } | |
| } else if (get_bits1(&gb)) { | |
| if (get_bits1(&gb)) { | |
| y_avg = get_bits(&gb, 6); | |
| } else { | |
| unsigned adjust_index = get_bits(&gb, 3); | |
| y_avg = (y_avg + luma_adjust[adjust_index]) & 63; | |
| } | |
| for (i = 0; i < 4; i++) | |
| y[i] = y_avg; | |
| } | |
| if (get_bits1(&gb)) { | |
| if (get_bits1(&gb)) { | |
| cb = get_bits(&gb, 5); | |
| cr = get_bits(&gb, 5); | |
| } else { | |
| unsigned adjust_index = get_bits(&gb, 3); | |
| cb = (cb + chroma_adjust[0][adjust_index]) & 31; | |
| cr = (cr + chroma_adjust[1][adjust_index]) & 31; | |
| } | |
| } | |
| } | |
| *ya++ = y_avg; | |
| new_y[0] = y[0]; | |
| new_y[1] = y[1]; | |
| new_y[new_y_stride] = y[2]; | |
| new_y[new_y_stride + 1] = y[3]; | |
| *new_cb = cb; | |
| *new_cr = cr; | |
| old_y += 2; | |
| old_cb++; | |
| old_cr++; | |
| new_y += 2; | |
| new_cb++; | |
| new_cr++; | |
| block_x++; | |
| if (block_x * 2 == avctx->width) { | |
| block_x = 0; | |
| old_y += old_y_stride * 2 - avctx->width; | |
| old_cb += old_cb_stride - avctx->width / 2; | |
| old_cr += old_cr_stride - avctx->width / 2; | |
| new_y += new_y_stride * 2 - avctx->width; | |
| new_cb += new_cb_stride - avctx->width / 2; | |
| new_cr += new_cr_stride - avctx->width / 2; | |
| } | |
| skip--; | |
| } | |
| new_y = s->new_y; | |
| new_cb = s->new_u; | |
| new_cr = s->new_v; | |
| dstY = pic->data[0]; | |
| dstU = pic->data[1]; | |
| dstV = pic->data[2]; | |
| for (j = 0; j < avctx->height; j++) { | |
| for (i = 0; i < avctx->width; i++) | |
| dstY[i] = new_y[i] << 2; | |
| dstY += pic->linesize[0]; | |
| new_y += new_y_stride; | |
| } | |
| for (j = 0; j < avctx->height / 2; j++) { | |
| for (i = 0; i < avctx->width / 2; i++) { | |
| dstU[i] = chroma_vals[new_cb[i]]; | |
| dstV[i] = chroma_vals[new_cr[i]]; | |
| } | |
| dstU += pic->linesize[1]; | |
| dstV += pic->linesize[2]; | |
| new_cb += new_cb_stride; | |
| new_cr += new_cr_stride; | |
| } | |
| ff_dlog(avctx, "Frame data: provided %d bytes, used %d bytes\n", | |
| buf_size, get_bits_count(&gb) >> 3); | |
| FFSWAP(uint8_t*, s->old_y, s->new_y); | |
| FFSWAP(uint8_t*, s->old_u, s->new_u); | |
| FFSWAP(uint8_t*, s->old_v, s->new_v); | |
| *got_frame = 1; | |
| return buf_size; | |
| } | |
| const FFCodec ff_escape130_decoder = { | |
| .p.name = "escape130", | |
| CODEC_LONG_NAME("Escape 130"), | |
| .p.type = AVMEDIA_TYPE_VIDEO, | |
| .p.id = AV_CODEC_ID_ESCAPE130, | |
| .priv_data_size = sizeof(Escape130Context), | |
| .init = escape130_decode_init, | |
| .close = escape130_decode_close, | |
| FF_CODEC_DECODE_CB(escape130_decode_frame), | |
| .p.capabilities = AV_CODEC_CAP_DR1, | |
| .caps_internal = FF_CODEC_CAP_INIT_CLEANUP, | |
| }; |