/* * Copyright (C) 2005 Ole André Vadla Ravnås * Copyright (C) 2008 Ramiro Polla * * 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 #include "libavutil/mem.h" #include "libavutil/mem_internal.h" #include "libavutil/thread.h" #include "avcodec.h" #include "blockdsp.h" #include "codec_internal.h" #include "decode.h" #include "get_bits.h" #include "bytestream.h" #include "bswapdsp.h" #include "hpeldsp.h" #include "idctdsp.h" #include "progressframe.h" #include "thread.h" #define MIMIC_HEADER_SIZE 20 #define MIMIC_VLC_BITS 11 typedef struct MimicContext { AVCodecContext *avctx; int num_vblocks[3]; int num_hblocks[3]; void *swap_buf; int swap_buf_size; int cur_index; int prev_index; ProgressFrame frames[16]; DECLARE_ALIGNED(32, int16_t, dct_block)[64]; GetBitContext gb; uint8_t permutated_scantable[64]; BlockDSPContext bdsp; BswapDSPContext bbdsp; HpelDSPContext hdsp; IDCTDSPContext idsp; /* Kept in the context so multithreading can have a constant to read from */ int next_cur_index; int next_prev_index; } MimicContext; static VLCElem block_vlc[4368]; static const uint8_t huffsyms[] = { 0x10, 0x20, 0x30, 0x00, 0x11, 0x40, 0x50, 0x12, 0x13, 0x21, 0x31, 0x60, 0x14, 0x15, 0x16, 0x22, 0x41, 0x17, 0x18, 0x23, 0x24, 0x25, 0x32, 0x42, 0x51, 0x61, 0x70, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, }; static const uint8_t huffbits[] = { 2, 2, 3, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 22, 23, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 27, 28, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30, }; static const uint8_t col_zag[64] = { 0, 8, 1, 2, 9, 16, 24, 17, 10, 3, 4, 11, 18, 25, 32, 40, 33, 26, 19, 12, 5, 6, 13, 20, 27, 34, 41, 48, 56, 49, 42, 35, 28, 21, 14, 7, 15, 22, 29, 36, 43, 50, 57, 58, 51, 44, 37, 30, 23, 31, 38, 45, 52, 59, 39, 46, 53, 60, 61, 54, 47, 55, 62, 63, }; static av_cold int mimic_decode_end(AVCodecContext *avctx) { MimicContext *ctx = avctx->priv_data; av_freep(&ctx->swap_buf); ctx->swap_buf_size = 0; for (int i = 0; i < FF_ARRAY_ELEMS(ctx->frames); i++) ff_progress_frame_unref(&ctx->frames[i]); return 0; } static av_cold void mimic_init_static(void) { VLC_INIT_STATIC_TABLE_FROM_LENGTHS(block_vlc, MIMIC_VLC_BITS, FF_ARRAY_ELEMS(huffbits), huffbits, 1, huffsyms, 1, 1, 0, 0); } static av_cold int mimic_decode_init(AVCodecContext *avctx) { static AVOnce init_static_once = AV_ONCE_INIT; MimicContext *ctx = avctx->priv_data; ctx->prev_index = 0; ctx->cur_index = 15; ff_blockdsp_init(&ctx->bdsp); ff_bswapdsp_init(&ctx->bbdsp); ff_hpeldsp_init(&ctx->hdsp, avctx->flags); ff_idctdsp_init(&ctx->idsp, avctx); ff_permute_scantable(ctx->permutated_scantable, col_zag, ctx->idsp.idct_permutation); ff_thread_once(&init_static_once, mimic_init_static); return 0; } #if HAVE_THREADS static int mimic_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from) { MimicContext *dst = avctx->priv_data, *src = avctx_from->priv_data; if (avctx == avctx_from) return 0; dst->cur_index = src->next_cur_index; dst->prev_index = src->next_prev_index; for (int i = 0; i < FF_ARRAY_ELEMS(dst->frames); i++) { ff_progress_frame_unref(&dst->frames[i]); if (i != src->next_cur_index && src->frames[i].f) ff_progress_frame_ref(&dst->frames[i], &src->frames[i]); } return 0; } #endif static const int8_t vlcdec_lookup[9][64] = { { 0, }, { -1, 1, }, { -3, 3, -2, 2, }, { -7, 7, -6, 6, -5, 5, -4, 4, }, { -15, 15, -14, 14, -13, 13, -12, 12, -11, 11, -10, 10, -9, 9, -8, 8, }, { -31, 31, -30, 30, -29, 29, -28, 28, -27, 27, -26, 26, -25, 25, -24, 24, -23, 23, -22, 22, -21, 21, -20, 20, -19, 19, -18, 18, -17, 17, -16, 16, }, { -63, 63, -62, 62, -61, 61, -60, 60, -59, 59, -58, 58, -57, 57, -56, 56, -55, 55, -54, 54, -53, 53, -52, 52, -51, 51, -50, 50, -49, 49, -48, 48, -47, 47, -46, 46, -45, 45, -44, 44, -43, 43, -42, 42, -41, 41, -40, 40, -39, 39, -38, 38, -37, 37, -36, 36, -35, 35, -34, 34, -33, 33, -32, 32, }, { -127, 127, -126, 126, -125, 125, -124, 124, -123, 123, -122, 122, -121, 121, -120, 120, -119, 119, -118, 118, -117, 117, -116, 116, -115, 115, -114, 114, -113, 113, -112, 112, -111, 111, -110, 110, -109, 109, -108, 108, -107, 107, -106, 106, -105, 105, -104, 104, -103, 103, -102, 102, -101, 101, -100, 100, -99, 99, -98, 98, -97, 97, -96, 96, }, { -95, 95, -94, 94, -93, 93, -92, 92, -91, 91, -90, 90, -89, 89, -88, 88, -87, 87, -86, 86, -85, 85, -84, 84, -83, 83, -82, 82, -81, 81, -80, 80, -79, 79, -78, 78, -77, 77, -76, 76, -75, 75, -74, 74, -73, 73, -72, 72, -71, 71, -70, 70, -69, 69, -68, 68, -67, 67, -66, 66, -65, 65, -64, 64, }, }; static int vlc_decode_block(MimicContext *ctx, int num_coeffs, int qscale) { int16_t *block = ctx->dct_block; unsigned int pos; ctx->bdsp.clear_block(block); block[0] = get_bits(&ctx->gb, 8) << 3; for (pos = 1; pos < num_coeffs; pos++) { uint32_t vlc, num_bits; int value; int coeff; vlc = get_vlc2(&ctx->gb, block_vlc, MIMIC_VLC_BITS, 3); if (!vlc) /* end-of-block code */ return 0; if (vlc == -1) return AVERROR_INVALIDDATA; /* pos_add and num_bits are coded in the vlc code */ pos += vlc & 15; // pos_add num_bits = vlc >> 4; // num_bits if (pos >= 64) return AVERROR_INVALIDDATA; value = get_bits(&ctx->gb, num_bits); /* FFmpeg's IDCT behaves somewhat different from the original code, so * a factor of 4 was added to the input */ coeff = ((int8_t*)vlcdec_lookup[num_bits])[value]; if (pos < 3) coeff *= 16; else /* TODO Use >> 10 instead of / 1001 */ coeff = (coeff * qscale) / 1001; block[ctx->permutated_scantable[pos]] = coeff; } return 0; } static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe) { int ret, y, x, plane, cur_row = 0; for (plane = 0; plane < 3; plane++) { const int is_chroma = !!plane; const int qscale = av_clip(10000 - quality, is_chroma ? 1000 : 2000, 10000) << 2; const int stride = ctx->frames[ctx->cur_index ].f->linesize[plane]; uint8_t *dst = ctx->frames[ctx->cur_index ].f->data[plane]; /* src is unused for I frames; set to avoid UB pointer arithmetic. */ const uint8_t *src = is_iframe ? dst : ctx->frames[ctx->prev_index].f->data[plane]; for (y = 0; y < ctx->num_vblocks[plane]; y++) { for (x = 0; x < ctx->num_hblocks[plane]; x++) { /* Check for a change condition in the current block. * - iframes always change. * - Luma plane changes on get_bits1 == 0 * - Chroma planes change on get_bits1 == 1 */ if (is_iframe || get_bits1(&ctx->gb) == is_chroma) { /* Luma planes may use a backreference from the 15 last * frames preceding the previous. (get_bits1 == 1) * Chroma planes don't use backreferences. */ if (is_chroma || is_iframe || !get_bits1(&ctx->gb)) { if ((ret = vlc_decode_block(ctx, num_coeffs, qscale)) < 0) { av_log(ctx->avctx, AV_LOG_ERROR, "Error decoding " "block.\n"); return ret; } ctx->idsp.idct_put(dst, stride, ctx->dct_block); } else { unsigned int backref = get_bits(&ctx->gb, 4); int index = (ctx->cur_index + backref) & 15; if (index != ctx->cur_index && ctx->frames[index].f) { const uint8_t *p = ctx->frames[index].f->data[0]; ff_progress_frame_await(&ctx->frames[index], cur_row); p += src - ctx->frames[ctx->prev_index].f->data[plane]; ctx->hdsp.put_pixels_tab[1][0](dst, p, stride, 8); } else { av_log(ctx->avctx, AV_LOG_ERROR, "No such backreference! Buggy sample.\n"); } } } else { ff_progress_frame_await(&ctx->frames[ctx->prev_index], cur_row); ctx->hdsp.put_pixels_tab[1][0](dst, src, stride, 8); } src += 8; dst += 8; } src += (stride - ctx->num_hblocks[plane]) << 3; dst += (stride - ctx->num_hblocks[plane]) << 3; ff_progress_frame_report(&ctx->frames[ctx->cur_index], cur_row++); } } return 0; } /** * Flip the buffer upside-down and put it in the YVU order to revert the * way Mimic encodes frames. */ static void flip_swap_frame(AVFrame *f) { int i; uint8_t *data_1 = f->data[1]; f->data[0] = f->data[0] + ( f->height - 1) * f->linesize[0]; f->data[1] = f->data[2] + ((f->height >> 1) - 1) * f->linesize[2]; f->data[2] = data_1 + ((f->height >> 1) - 1) * f->linesize[1]; for (i = 0; i < 3; i++) f->linesize[i] *= -1; } static int mimic_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; int swap_buf_size = buf_size - MIMIC_HEADER_SIZE; MimicContext *ctx = avctx->priv_data; GetByteContext gb; int is_pframe; int width, height; int quality, num_coeffs; int res; if (buf_size <= MIMIC_HEADER_SIZE) { av_log(avctx, AV_LOG_ERROR, "insufficient data\n"); return AVERROR_INVALIDDATA; } bytestream2_init(&gb, buf, MIMIC_HEADER_SIZE); bytestream2_skip(&gb, 2); /* some constant (always 256) */ quality = bytestream2_get_le16u(&gb); width = bytestream2_get_le16u(&gb); height = bytestream2_get_le16u(&gb); bytestream2_skip(&gb, 4); /* some constant */ is_pframe = bytestream2_get_le32u(&gb); num_coeffs = bytestream2_get_byteu(&gb); bytestream2_skip(&gb, 3); /* some constant */ if (!ctx->avctx) { int i; if (!(width == 160 && height == 120) && !(width == 320 && height == 240)) { av_log(avctx, AV_LOG_ERROR, "invalid width/height!\n"); return AVERROR_INVALIDDATA; } res = ff_set_dimensions(avctx, width, height); if (res < 0) return res; ctx->avctx = avctx; avctx->pix_fmt = AV_PIX_FMT_YUV420P; for (i = 0; i < 3; i++) { ctx->num_vblocks[i] = AV_CEIL_RSHIFT(height, 3 + !!i); ctx->num_hblocks[i] = width >> (3 + !!i); } } else if (width != ctx->avctx->width || height != ctx->avctx->height) { avpriv_request_sample(avctx, "Resolution changing"); return AVERROR_PATCHWELCOME; } if (is_pframe && !ctx->frames[ctx->prev_index].f) { av_log(avctx, AV_LOG_ERROR, "decoding must start with keyframe\n"); return AVERROR_INVALIDDATA; } ff_progress_frame_unref(&ctx->frames[ctx->cur_index]); res = ff_progress_frame_get_buffer(avctx, &ctx->frames[ctx->cur_index], AV_GET_BUFFER_FLAG_REF); if (res < 0) return res; ctx->frames[ctx->cur_index].f->pict_type = is_pframe ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I; ctx->next_prev_index = ctx->cur_index; ctx->next_cur_index = (ctx->cur_index - 1) & 15; ff_thread_finish_setup(avctx); av_fast_padded_malloc(&ctx->swap_buf, &ctx->swap_buf_size, swap_buf_size); if (!ctx->swap_buf) return AVERROR(ENOMEM); ctx->bbdsp.bswap_buf(ctx->swap_buf, (const uint32_t *) (buf + MIMIC_HEADER_SIZE), swap_buf_size >> 2); init_get_bits(&ctx->gb, ctx->swap_buf, swap_buf_size << 3); res = decode(ctx, quality, num_coeffs, !is_pframe); ff_progress_frame_report(&ctx->frames[ctx->cur_index], INT_MAX); if (res < 0) { if (!(avctx->active_thread_type & FF_THREAD_FRAME)) ff_progress_frame_unref(&ctx->frames[ctx->cur_index]); return res; } if ((res = av_frame_ref(rframe, ctx->frames[ctx->cur_index].f)) < 0) return res; *got_frame = 1; flip_swap_frame(rframe); ctx->prev_index = ctx->next_prev_index; ctx->cur_index = ctx->next_cur_index; return buf_size; } const FFCodec ff_mimic_decoder = { .p.name = "mimic", CODEC_LONG_NAME("Mimic"), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_MIMIC, .priv_data_size = sizeof(MimicContext), .init = mimic_decode_init, .close = mimic_decode_end, FF_CODEC_DECODE_CB(mimic_decode_frame), .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS, UPDATE_THREAD_CONTEXT(mimic_decode_update_thread_context), .caps_internal = FF_CODEC_CAP_USES_PROGRESSFRAMES | FF_CODEC_CAP_INIT_CLEANUP, };