vlog.debug("Received %u bytes, decoding", len);
+ // extract actual size, including possible cropping
+ ParseSPS(h264_buffer, len);
+
if (FAILED(decoder->ProcessInput(0, input_sample, 0)))
{
vlog.error("Error sending a packet to decoding");
// reinitialize output type (NV12) that now has correct properties (width/height/framerate)
decoder->SetOutputType(0, output_type, 0);
- UINT32 width = 0;
- UINT32 height = 0;
- MFGetAttributeSize(output_type, MF_MT_FRAME_SIZE, &width, &height);
- vlog.debug("Setting up decoded output with %ux%u size", width, height);
+ UINT32 width, height;
+ if FAILED(MFGetAttributeSize(output_type, MF_MT_FRAME_SIZE, &width, &height))
+ {
+ vlog.error("Error getting output type size");
+ output_type->Release();
+ break;
+ }
+
+ // if MFT reports different width or height than calculated cropped width/height
+ if (crop_width != 0 && crop_height != 0 && (width != crop_width || height != crop_height))
+ {
+ // create NV12/RGB image with full size as we'll do manual cropping
+ width = full_width;
+ height = full_height;
+ }
+ else
+ {
+ // no manual cropping necessary
+ offset_x = offset_y = 0;
+ crop_width = width;
+ crop_height = height;
+ }
+
+ vlog.debug("Setting up decoded output with %ux%u size", crop_width, crop_height);
// input type to converter, BGRX pixel format
IMFMediaType* converted_type;
converted_type->SetGUID(MF_MT_MAJOR_TYPE, MFMediaType_Video);
converted_type->SetGUID(MF_MT_SUBTYPE, MFVideoFormat_RGB32);
converted_type->SetUINT32(MF_MT_INTERLACE_MODE, MFVideoInterlace_Progressive);
- MFSetAttributeSize(converted_type, MF_MT_FRAME_SIZE, width, height);
- MFGetStrideForBitmapInfoHeader(MFVideoFormat_RGB32.Data1, width, &stride);
+ MFSetAttributeSize(converted_type, MF_MT_FRAME_SIZE, full_width, full_height);
+ MFGetStrideForBitmapInfoHeader(MFVideoFormat_RGB32.Data1, full_width, &stride);
// bottom-up
stride = -stride;
converted_type->SetUINT32(MF_MT_DEFAULT_STRIDE, (UINT32)stride);
vlog.debug("Frame converted to RGB");
BYTE* out;
- converted_buffer->Lock(&out, NULL, NULL);
- pb->imageRect(rect, out, (int)stride / 4);
+ DWORD len;
+ converted_buffer->Lock(&out, NULL, &len);
+ pb->imageRect(rect, out + offset_y * stride + offset_x * 4, (int)stride / 4);
converted_buffer->Unlock();
}
}
}
+
+// "7.3.2.1.1 Sequence parameter set data syntax" on page 66 of https://www.itu.int/rec/T-REC-H.264-202108-I/en
+void H264WinDecoderContext::ParseSPS(const rdr::U8* buffer, int length)
+{
+#define EXPECT(cond) if (!(cond)) return;
+
+#define GET_BIT(bit) do { \
+ if (available == 0) \
+ { \
+ if (length == 0) return; \
+ byte = *buffer++; \
+ length--; \
+ available = 8; \
+ } \
+ bit = (byte >> --available) & 1; \
+} while (0)
+
+#define GET_BITS(n, var) do { \
+ var = 0; \
+ for (int i = n-1; i >= 0; i--) \
+ { \
+ unsigned bit; \
+ GET_BIT(bit); \
+ var |= bit << i; \
+ } \
+} while (0)
+
+// "9.1 Parsing process for Exp-Golomb codes" on page 231
+
+#define GET_UE(var) do { \
+ int zeroes = -1; \
+ for (unsigned bit = 0; !bit; zeroes++) \
+ GET_BIT(bit); \
+ GET_BITS(zeroes, var); \
+ var += (1U << zeroes) - 1; \
+} while(0)
+
+#define SKIP_UE() do { \
+ unsigned var; \
+ GET_UE(var); \
+} while (0)
+
+#define SKIP_BITS(bits) do { \
+ unsigned var; \
+ GET_BITS(bits, var); \
+} while (0)
+
+ // check for NAL header
+ EXPECT((length >= 3 && buffer[0] == 0 && buffer[1] == 0 && buffer[2] == 1) ||
+ (length >= 4 && buffer[0] == 0 && buffer[1] == 0 && buffer[2] == 0 && buffer[3] == 1));
+ length -= 4 - buffer[2];
+ buffer += 4 - buffer[2];
+
+ // NAL unit type
+ EXPECT(length > 1);
+ rdr::U8 type = buffer[0];
+ EXPECT((type & 0x80) == 0); // forbidden zero bit
+ EXPECT((type & 0x1f) == 7); // SPS NAL unit type
+ buffer++;
+ length--;
+
+ int available = 0;
+ rdr::U8 byte = 0;
+
+ unsigned profile_idc;
+ unsigned seq_parameter_set_id;
+
+ GET_BITS(8, profile_idc);
+ SKIP_BITS(6); // constraint_set0..5_flag
+ SKIP_BITS(2); // reserved_zero_2bits
+ SKIP_BITS(8); // level_idc
+ GET_UE(seq_parameter_set_id);
+
+ unsigned chroma_format_idc = 1;
+ if (profile_idc == 100 || profile_idc == 110 ||
+ profile_idc == 122 || profile_idc == 244 ||
+ profile_idc == 44 || profile_idc == 83 ||
+ profile_idc == 86 || profile_idc == 118 ||
+ profile_idc == 128 || profile_idc == 138 ||
+ profile_idc == 139 || profile_idc == 134 ||
+ profile_idc == 135)
+ {
+ GET_UE(chroma_format_idc);
+ if (chroma_format_idc == 3)
+ {
+ SKIP_BITS(1); // separate_colour_plane_flag
+ }
+ SKIP_UE(); // bit_depth_luma_minus8
+ SKIP_UE(); // bit_depth_chroma_minus8;
+ SKIP_BITS(1); // qpprime_y_zero_transform_bypass_flag
+ unsigned seq_scaling_matrix_present_flag;
+ GET_BITS(1, seq_scaling_matrix_present_flag);
+ if (seq_scaling_matrix_present_flag)
+ {
+ for (int i = 0; i < (chroma_format_idc != 3 ? 8 : 12); i++)
+ {
+ int seq_scaling_list_present_flag;
+ GET_BITS(1, seq_scaling_list_present_flag);
+ for (int j = 0; j < (seq_scaling_list_present_flag ? 16 : 64); j++)
+ {
+ SKIP_UE(); // delta_scale;
+ }
+ }
+ }
+ }
+
+ unsigned log2_max_frame_num_minus4;
+ GET_UE(log2_max_frame_num_minus4); // log2_max_frame_num_minus4
+ unsigned pic_order_cnt_type;
+ GET_UE(pic_order_cnt_type);
+ if (pic_order_cnt_type == 0)
+ {
+ SKIP_UE(); // log2_max_pic_order_cnt_lsb_minus4
+ }
+ else if (pic_order_cnt_type == 1)
+ {
+ SKIP_BITS(1); // delta_pic_order_always_zero_flag
+ SKIP_UE(); // offset_for_non_ref_pic
+ SKIP_UE(); // offset_for_top_to_bottom_field
+ unsigned num_ref_frames_in_pic_order_cnt_cycle;
+ GET_UE(num_ref_frames_in_pic_order_cnt_cycle);
+ for (unsigned i = 0; i < num_ref_frames_in_pic_order_cnt_cycle; i++)
+ {
+ SKIP_UE(); // offset_for_ref_frame
+ }
+ }
+ SKIP_UE(); // max_num_ref_frames
+ SKIP_BITS(1); // gaps_in_frame_num_value_allowed_flag
+ unsigned pic_width_in_mbs_minus1;
+ GET_UE(pic_width_in_mbs_minus1);
+ unsigned pic_height_in_map_units_minus1;
+ GET_UE(pic_height_in_map_units_minus1);
+ unsigned frame_mbs_only_flag;
+ GET_BITS(1, frame_mbs_only_flag);
+ if (!frame_mbs_only_flag)
+ {
+ SKIP_BITS(1); // mb_adaptive_frame_field_flag
+ }
+ SKIP_BITS(1); // direct_8x8_inference_flag
+ unsigned frame_cropping_flag;
+ GET_BITS(1, frame_cropping_flag);
+
+ unsigned frame_crop_left_offset = 0;
+ unsigned frame_crop_right_offset = 0;
+ unsigned frame_crop_top_offset = 0;
+ unsigned frame_crop_bottom_offset = 0;
+ if (frame_cropping_flag)
+ {
+ GET_UE(frame_crop_left_offset);
+ GET_UE(frame_crop_right_offset);
+ GET_UE(frame_crop_top_offset);
+ GET_UE(frame_crop_bottom_offset);
+ }
+ // ignore rest of bits
+
+ full_width = 16 * (pic_width_in_mbs_minus1 + 1);
+ full_height = 16 * (pic_height_in_map_units_minus1 + 1) * (2 - frame_mbs_only_flag);
+
+ // "6.2 Source, decoded, and output picture formats" on page 44
+ unsigned sub_width_c = (chroma_format_idc == 1 || chroma_format_idc == 2) ? 2 : 1;
+ unsigned sub_height_c = (chroma_format_idc == 1) ? 2 : 1;
+
+ // page 101
+ unsigned crop_unit_x = chroma_format_idc == 0 ? 1 : sub_width_c;
+ unsigned crop_unit_y = chroma_format_idc == 0 ? 2 - frame_mbs_only_flag : sub_height_c * (2 - frame_mbs_only_flag);
+ crop_width = full_width - crop_unit_x * (frame_crop_right_offset + frame_crop_left_offset);
+ crop_height = full_height - crop_unit_y * (frame_crop_top_offset + frame_crop_bottom_offset);
+
+ offset_x = frame_crop_left_offset;
+ offset_y = frame_crop_bottom_offset;
+
+ vlog.debug("SPS parsing - full=%dx%d, cropped=%dx%d, offset=%d,%d", full_width, full_height, crop_width, crop_height, offset_x, offset_y);
+
+#undef SKIP_BITS
+#undef SKIP_UE
+#undef GET_BITS
+#undef GET_BIT
+#undef GET_UE
+#undef EXPECT
+}
projects / tigervnc.git / commitdiff