/* * MidiVid MV30 decoder * * Copyright (c) 2020 Paul B Mahol * * 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 <stddef.h> #include <string.h> #include "libavutil/thread.h" #include "avcodec.h" #include "bytestream.h" #include "codec_internal.h" #include "copy_block.h" #include "decode.h" #include "mathops.h" #include "blockdsp.h" #include "get_bits.h" #include "aandcttab.h" #define CBP_VLC_BITS 9 typedef struct MV30Context { GetBitContext gb; int intra_quant; int inter_quant; int is_inter; int mode_size; int nb_mvectors; int block[6][64]; int16_t *mvectors; unsigned int mvectors_size; int16_t *coeffs; unsigned int coeffs_size; int16_t intraq_tab[2][64]; int16_t interq_tab[2][64]; BlockDSPContext bdsp; AVFrame *prev_frame; } MV30Context; static VLC cbp_tab; static const uint8_t luma_tab[] = { 12, 12, 15, 19, 25, 34, 40, 48, 12, 12, 18, 22, 27, 44, 47, 46, 17, 18, 21, 26, 35, 46, 52, 47, 18, 20, 24, 28, 40, 61, 59, 51, 20, 24, 32, 43, 50, 72, 72, 63, 25, 31, 42, 48, 58, 72, 81, 75, 38, 46, 54, 61, 71, 84, 88, 85, 50, 61, 65, 68, 79, 78, 86, 91, }; static const uint8_t chroma_tab[] = { 12, 16, 24, 47, 99, 99, 99, 99, 16, 21, 26, 66, 99, 99, 99, 99, 24, 26, 56, 99, 99, 99, 99, 99, 47, 66, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, }; static const uint8_t zigzag[] = { 0, 1, 8, 9, 16, 2, 3, 10, 17, 24, 32, 25, 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, 27, 20, 13, 6, 7, 14, 21, 28, 35, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, 30, 37, 44, 51, 58, 59, 52, 45, 38, 31, 39, 46, 53, 60, 61, 54, 47, 55, 62, 63, }; static void get_qtable(int16_t *table, int quant, const uint8_t *quant_tab) { int factor = quant < 50 ? 5000 / FFMAX(quant, 1) : 200 - FFMIN(quant, 100) * 2; for (int i = 0; i < 64; i++) { table[i] = av_clip((quant_tab[i] * factor + 0x32) / 100, 1, 0x7fff); table[i] = ((int)ff_aanscales[i] * (int)table[i] + 0x800) >> 12; } } static inline void idct_1d(unsigned *blk, int step) { const unsigned t0 = blk[0 * step] + blk[4 * step]; const unsigned t1 = blk[0 * step] - blk[4 * step]; const unsigned t2 = blk[2 * step] + blk[6 * step]; const unsigned t3 = ((int)((blk[2 * step] - blk[6 * step]) * 362U) >> 8) - t2; const unsigned t4 = t0 + t2; const unsigned t5 = t0 - t2; const unsigned t6 = t1 + t3; const unsigned t7 = t1 - t3; const unsigned t8 = blk[5 * step] + blk[3 * step]; const unsigned t9 = blk[5 * step] - blk[3 * step]; const unsigned tA = blk[1 * step] + blk[7 * step]; const unsigned tB = blk[1 * step] - blk[7 * step]; const unsigned tC = t8 + tA; const unsigned tD = (int)((tB + t9) * 473U) >> 8; const unsigned tE = (((int)(t9 * -669U) >> 8) - tC) + tD; const unsigned tF = ((int)((tA - t8) * 362U) >> 8) - tE; const unsigned t10 = (((int)(tB * 277U) >> 8) - tD) + tF; blk[0 * step] = t4 + tC; blk[1 * step] = t6 + tE; blk[2 * step] = t7 + tF; blk[3 * step] = t5 - t10; blk[4 * step] = t5 + t10; blk[5 * step] = t7 - tF; blk[6 * step] = t6 - tE; blk[7 * step] = t4 - tC; } static void idct_put(uint8_t *dst, int stride, int *block) { for (int i = 0; i < 8; i++) { if ((block[0x08 + i] | block[0x10 + i] | block[0x18 + i] | block[0x20 + i] | block[0x28 + i] | block[0x30 + i] | block[0x38 + i]) == 0) { block[0x08 + i] = block[i]; block[0x10 + i] = block[i]; block[0x18 + i] = block[i]; block[0x20 + i] = block[i]; block[0x28 + i] = block[i]; block[0x30 + i] = block[i]; block[0x38 + i] = block[i]; } else { idct_1d(block + i, 8); } } for (int i = 0; i < 8; i++) { idct_1d(block, 1); for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[j] >> 5) + 128); block += 8; dst += stride; } } static void idct_add(uint8_t *dst, int stride, const uint8_t *src, int in_linesize, int *block) { for (int i = 0; i < 8; i++) { if ((block[0x08 + i] | block[0x10 + i] | block[0x18 + i] | block[0x20 + i] | block[0x28 + i] | block[0x30 + i] | block[0x38 + i]) == 0) { block[0x08 + i] = block[i]; block[0x10 + i] = block[i]; block[0x18 + i] = block[i]; block[0x20 + i] = block[i]; block[0x28 + i] = block[i]; block[0x30 + i] = block[i]; block[0x38 + i] = block[i]; } else { idct_1d(block + i, 8); } } for (int i = 0; i < 8; i++) { idct_1d(block, 1); for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[j] >> 5) + src[j]); block += 8; dst += stride; src += in_linesize; } } static inline void idct2_1d(int *blk, int step) { const unsigned int t0 = blk[0 * step]; const unsigned int t1 = blk[1 * step]; const unsigned int t2 = (int)(t1 * 473U) >> 8; const unsigned int t3 = t2 - t1; const unsigned int t4 = ((int)(t1 * 362U) >> 8) - t3; const unsigned int t5 = (((int)(t1 * 277U) >> 8) - t2) + t4; blk[0 * step] = t1 + t0; blk[1 * step] = t0 + t3; blk[2 * step] = t4 + t0; blk[3 * step] = t0 - t5; blk[4 * step] = t5 + t0; blk[5 * step] = t0 - t4; blk[6 * step] = t0 - t3; blk[7 * step] = t0 - t1; } static void idct2_put(uint8_t *dst, int stride, int *block) { for (int i = 0; i < 2; i++) { if ((block[0x08 + i]) == 0) { block[0x08 + i] = block[i]; block[0x10 + i] = block[i]; block[0x18 + i] = block[i]; block[0x20 + i] = block[i]; block[0x28 + i] = block[i]; block[0x30 + i] = block[i]; block[0x38 + i] = block[i]; } else { idct2_1d(block + i, 8); } } for (int i = 0; i < 8; i++) { if (block[1] == 0) { for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[0] >> 5) + 128); } else { idct2_1d(block, 1); for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[j] >> 5) + 128); } block += 8; dst += stride; } } static void idct2_add(uint8_t *dst, int stride, const uint8_t *src, int in_linesize, int *block) { for (int i = 0; i < 2; i++) { if ((block[0x08 + i]) == 0) { block[0x08 + i] = block[i]; block[0x10 + i] = block[i]; block[0x18 + i] = block[i]; block[0x20 + i] = block[i]; block[0x28 + i] = block[i]; block[0x30 + i] = block[i]; block[0x38 + i] = block[i]; } else { idct2_1d(block + i, 8); } } for (int i = 0; i < 8; i++) { if (block[1] == 0) { for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[0] >> 5) + src[j]); } else { idct2_1d(block, 1); for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8((block[j] >> 5) + src[j]); } block += 8; dst += stride; src += in_linesize; } } static void update_inter_block(uint8_t *dst, int stride, const uint8_t *src, int in_linesize, int block) { for (int i = 0; i < 8; i++) { for (int j = 0; j < 8; j++) dst[j] = av_clip_uint8(block + src[j]); dst += stride; src += in_linesize; } } static int decode_intra_block(AVCodecContext *avctx, int mode, GetByteContext *gbyte, int16_t *qtab, int *block, int *pfill, uint8_t *dst, int linesize) { MV30Context *s = avctx->priv_data; int fill; switch (mode) { case 0: s->bdsp.fill_block_tab[1](dst, 128, linesize, 8); break; case 1: fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = ((int)((unsigned)pfill[0] * qtab[0]) >> 5) + 128; s->bdsp.fill_block_tab[1](dst, block[0], linesize, 8); break; case 2: memset(block, 0, sizeof(*block) * 64); fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = (unsigned)pfill[0] * qtab[0]; block[1] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[1]; block[8] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[8]; block[9] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[9]; idct2_put(dst, linesize, block); break; case 3: fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = (unsigned)pfill[0] * qtab[0]; for (int i = 1; i < 64; i++) block[zigzag[i]] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[zigzag[i]]; idct_put(dst, linesize, block); break; } return 0; } static int decode_inter_block(AVCodecContext *avctx, int mode, GetByteContext *gbyte, int16_t *qtab, int *block, int *pfill, uint8_t *dst, int linesize, const uint8_t *src, int in_linesize) { int fill; switch (mode) { case 0: copy_block8(dst, src, linesize, in_linesize, 8); break; case 1: fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = (int)((unsigned)pfill[0] * qtab[0]) >> 5; update_inter_block(dst, linesize, src, in_linesize, block[0]); break; case 2: memset(block, 0, sizeof(*block) * 64); fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = (unsigned)pfill[0] * qtab[0]; block[1] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[1]; block[8] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[8]; block[9] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[9]; idct2_add(dst, linesize, src, in_linesize, block); break; case 3: fill = sign_extend(bytestream2_get_ne16(gbyte), 16); pfill[0] += fill; block[0] = (unsigned)pfill[0] * qtab[0]; for (int i = 1; i < 64; i++) block[zigzag[i]] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[zigzag[i]]; idct_add(dst, linesize, src, in_linesize, block); break; } return 0; } static int decode_coeffs(GetBitContext *gb, int16_t *coeffs, int nb_codes) { memset(coeffs, 0, nb_codes * sizeof(*coeffs)); for (int i = 0; i < nb_codes;) { int value = get_vlc2(gb, cbp_tab.table, CBP_VLC_BITS, 1); if (value > 0) { int x = get_bits(gb, value); if (x < (1 << value) / 2) { x = (1 << (value - 1)) + (x & ((1 << value) - 1 >> 1)); } else { x = -(1 << (value - 1)) - (x & ((1 << value) - 1 >> 1)); } coeffs[i++] = x; } else { int flag = get_bits1(gb); i += get_bits(gb, 3 + flag * 3) + 1 + flag * 8; } } return 0; } static int decode_intra(AVCodecContext *avctx, GetBitContext *gb, AVFrame *frame) { MV30Context *s = avctx->priv_data; GetBitContext mgb; uint8_t *dst[6]; int linesize[6]; int ret; mgb = *gb; if (get_bits_left(gb) < s->mode_size * 8) return AVERROR_INVALIDDATA; skip_bits_long(gb, s->mode_size * 8); linesize[0] = frame->linesize[0]; linesize[1] = frame->linesize[0]; linesize[2] = frame->linesize[0]; linesize[3] = frame->linesize[0]; linesize[4] = frame->linesize[1]; linesize[5] = frame->linesize[2]; for (int y = 0; y < avctx->height; y += 16) { GetByteContext gbyte; int pfill[3][1] = { {0} }; int nb_codes = get_bits(gb, 16); av_fast_padded_malloc(&s->coeffs, &s->coeffs_size, nb_codes * sizeof(*s->coeffs)); if (!s->coeffs) return AVERROR(ENOMEM); ret = decode_coeffs(gb, s->coeffs, nb_codes); if (ret < 0) return ret; bytestream2_init(&gbyte, (uint8_t *)s->coeffs, nb_codes * sizeof(*s->coeffs)); for (int x = 0; x < avctx->width; x += 16) { dst[0] = frame->data[0] + linesize[0] * y + x; dst[1] = frame->data[0] + linesize[0] * y + x + 8; dst[2] = frame->data[0] + linesize[0] * (y + 8) + x; dst[3] = frame->data[0] + linesize[0] * (y + 8) + x + 8; dst[4] = frame->data[1] + linesize[4] * (y >> 1) + (x >> 1); dst[5] = frame->data[2] + linesize[5] * (y >> 1) + (x >> 1); for (int b = 0; b < 6; b++) { int mode = get_bits_le(&mgb, 2); ret = decode_intra_block(avctx, mode, &gbyte, s->intraq_tab[b >= 4], s->block[b], pfill[(b >= 4) + (b >= 5)], dst[b], linesize[b]); if (ret < 0) return ret; } } } return 0; } static int decode_inter(AVCodecContext *avctx, GetBitContext *gb, AVFrame *frame, AVFrame *prev) { MV30Context *s = avctx->priv_data; GetBitContext mask; GetBitContext mgb; GetByteContext mv; const int mask_size = ((avctx->height >> 4) * (avctx->width >> 4) * 2 + 7) / 8; uint8_t *dst[6], *src[6]; int in_linesize[6]; int linesize[6]; int ret, cnt = 0; int flags = 0; in_linesize[0] = prev->linesize[0]; in_linesize[1] = prev->linesize[0]; in_linesize[2] = prev->linesize[0]; in_linesize[3] = prev->linesize[0]; in_linesize[4] = prev->linesize[1]; in_linesize[5] = prev->linesize[2]; linesize[0] = frame->linesize[0]; linesize[1] = frame->linesize[0]; linesize[2] = frame->linesize[0]; linesize[3] = frame->linesize[0]; linesize[4] = frame->linesize[1]; linesize[5] = frame->linesize[2]; av_fast_padded_malloc(&s->mvectors, &s->mvectors_size, 2 * s->nb_mvectors * sizeof(*s->mvectors)); if (!s->mvectors) { ret = AVERROR(ENOMEM); goto fail; } mask = *gb; skip_bits_long(gb, mask_size * 8); mgb = *gb; skip_bits_long(gb, s->mode_size * 8); ret = decode_coeffs(gb, s->mvectors, 2 * s->nb_mvectors); if (ret < 0) goto fail; bytestream2_init(&mv, (uint8_t *)s->mvectors, 2 * s->nb_mvectors * sizeof(*s->mvectors)); for (int y = 0; y < avctx->height; y += 16) { GetByteContext gbyte; int pfill[3][1] = { {0} }; int nb_codes = get_bits(gb, 16); skip_bits(gb, 8); if (get_bits_left(gb) < 0) { ret = AVERROR_INVALIDDATA; goto fail; } av_fast_padded_malloc(&s->coeffs, &s->coeffs_size, nb_codes * sizeof(*s->coeffs)); if (!s->coeffs) { ret = AVERROR(ENOMEM); goto fail; } ret = decode_coeffs(gb, s->coeffs, nb_codes); if (ret < 0) goto fail; bytestream2_init(&gbyte, (uint8_t *)s->coeffs, nb_codes * sizeof(*s->coeffs)); for (int x = 0; x < avctx->width; x += 16) { if (cnt >= 4) cnt = 0; if (cnt == 0) { if (get_bits_left(&mask) < 8) { ret = AVERROR_INVALIDDATA; goto fail; } flags = get_bits(&mask, 8); } dst[0] = frame->data[0] + linesize[0] * y + x; dst[1] = frame->data[0] + linesize[0] * y + x + 8; dst[2] = frame->data[0] + linesize[0] * (y + 8) + x; dst[3] = frame->data[0] + linesize[0] * (y + 8) + x + 8; dst[4] = frame->data[1] + linesize[4] * (y >> 1) + (x >> 1); dst[5] = frame->data[2] + linesize[5] * (y >> 1) + (x >> 1); if ((flags >> (cnt)) & 1) { int mv_x = sign_extend(bytestream2_get_ne16(&mv), 16); int mv_y = sign_extend(bytestream2_get_ne16(&mv), 16); int px = x + mv_x; int py = y + mv_y; if (px < 0 || px > FFALIGN(avctx->width , 16) - 16 || py < 0 || py > FFALIGN(avctx->height, 16) - 16) return AVERROR_INVALIDDATA; src[0] = prev->data[0] + in_linesize[0] * py + px; src[1] = prev->data[0] + in_linesize[0] * py + px + 8; src[2] = prev->data[0] + in_linesize[0] * (py + 8) + px; src[3] = prev->data[0] + in_linesize[0] * (py + 8) + px + 8; src[4] = prev->data[1] + in_linesize[4] * (py >> 1) + (px >> 1); src[5] = prev->data[2] + in_linesize[5] * (py >> 1) + (px >> 1); if ((flags >> (cnt + 4)) & 1) { for (int b = 0; b < 6; b++) copy_block8(dst[b], src[b], linesize[b], in_linesize[b], 8); } else { for (int b = 0; b < 6; b++) { int mode = get_bits_le(&mgb, 2); ret = decode_inter_block(avctx, mode, &gbyte, s->interq_tab[b >= 4], s->block[b], pfill[(b >= 4) + (b >= 5)], dst[b], linesize[b], src[b], in_linesize[b]); if (ret < 0) goto fail; } } } else { for (int b = 0; b < 6; b++) { int mode = get_bits_le(&mgb, 2); ret = decode_intra_block(avctx, mode, &gbyte, s->intraq_tab[b >= 4], s->block[b], pfill[(b >= 4) + (b >= 5)], dst[b], linesize[b]); if (ret < 0) goto fail; } } cnt++; } } fail: return ret; } static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt) { MV30Context *s = avctx->priv_data; GetBitContext *gb = &s->gb; int ret; if ((ret = init_get_bits8(gb, avpkt->data, avpkt->size)) < 0) return ret; if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) return ret; s->intra_quant = get_bits(gb, 8); s->inter_quant = s->intra_quant + get_sbits(gb, 8); s->is_inter = get_bits_le(gb, 16); s->mode_size = get_bits_le(gb, 16); if (s->is_inter) s->nb_mvectors = get_bits_le(gb, 16); get_qtable(s->intraq_tab[0], s->intra_quant, luma_tab); get_qtable(s->intraq_tab[1], s->intra_quant, chroma_tab); frame->key_frame = s->is_inter == 0; if (frame->key_frame) { ret = decode_intra(avctx, gb, frame); if (ret < 0) return ret; } else { get_qtable(s->interq_tab[0], s->inter_quant, luma_tab); get_qtable(s->interq_tab[1], s->inter_quant, chroma_tab); if (!s->prev_frame->data[0]) { av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); return AVERROR_INVALIDDATA; } ret = decode_inter(avctx, gb, frame, s->prev_frame); if (ret < 0) return ret; } av_frame_unref(s->prev_frame); if ((ret = av_frame_ref(s->prev_frame, frame)) < 0) return ret; *got_frame = 1; return avpkt->size; } static const uint8_t cbp_bits[] = { 2, 2, 3, 3, 3, 4, 5, 6, 7, 8, 9, 9, }; static av_cold void init_static_data(void) { INIT_VLC_STATIC_FROM_LENGTHS(&cbp_tab, CBP_VLC_BITS, FF_ARRAY_ELEMS(cbp_bits), cbp_bits, 1, NULL, 0, 0, 0, 0, 1 << CBP_VLC_BITS); } static av_cold int decode_init(AVCodecContext *avctx) { MV30Context *s = avctx->priv_data; static AVOnce init_static_once = AV_ONCE_INIT; avctx->pix_fmt = AV_PIX_FMT_YUV420P; avctx->color_range = AVCOL_RANGE_JPEG; ff_blockdsp_init(&s->bdsp); s->prev_frame = av_frame_alloc(); if (!s->prev_frame) return AVERROR(ENOMEM); ff_thread_once(&init_static_once, init_static_data); return 0; } static void decode_flush(AVCodecContext *avctx) { MV30Context *s = avctx->priv_data; av_frame_unref(s->prev_frame); } static av_cold int decode_close(AVCodecContext *avctx) { MV30Context *s = avctx->priv_data; av_frame_free(&s->prev_frame); av_freep(&s->coeffs); s->coeffs_size = 0; av_freep(&s->mvectors); s->mvectors_size = 0; return 0; } const FFCodec ff_mv30_decoder = { .p.name = "mv30", CODEC_LONG_NAME("MidiVid 3.0"), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_MV30, .priv_data_size = sizeof(MV30Context), .init = decode_init, .close = decode_close, FF_CODEC_DECODE_CB(decode_frame), .flush = decode_flush, .p.capabilities = AV_CODEC_CAP_DR1, .caps_internal = FF_CODEC_CAP_INIT_CLEANUP, };